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rudeludenotmean
10-06-2007, 10:52 AM
OK .. So, yesterday, i did an OBD1 conversion on a 89 Accord LXi. The swap was made simple by an "already modified" distributor - but honestly, that where the ball stops rolling.

For the swap, ANY OBD1 distributor will work, but the Tabs must be cut off an re-welded (or any other type of method you know for reattaching metal pieces together). From what i understand, the CAM key is no longer at TDC after you realign the Mounting tabs (not first-hand information). Because of this, each Cam Key is going to need to be re-drilled in different spots (from stock), and drilling location is unique to how YOU mounted the Distibutor on YOUR engine. I cannot say "redrill the cam key here, and here" because those holes still might not be where your engine is at TDC. Again, redrilling is going to be unique to your setup, on your own Distributor, depending on how you decided to relocate the timing adjustment/Mounting tabs. DO REMEMBER -- Once you redrill the Cam key, and reset its postion to the correct TDC, firing order is going to be altered!!! (The Stock Firing order, 1, 3, 4, 2 will remain, but will have to be rotated a specific way on the distributor; again - unique to YOUR setup, for how YOU remounted the distributor; use common sense. *See below for more information - *thegreatdane gets credit for this edit). -- During the swap i performed, this issue was not outlined, and i had to use my brain to figure that out for myself. Dont make the same mistake, it WILL cause unnecessary headaches; believe me.

Ok .. after you have successfully setup your distributor, you have arrived at the simpler part.

Run 3 strands of wire to the inside of the car, under the carpet, over to the ECU (under the seat) It would be best if 2 of the wires were shielded, preventing unnecessary radio frequencies (emitted by the wires) from interfering with surrounding Audio equipment wires (such audio wires would have to be in VERY close proximity for this to happen); so using shielded wire is not THAT serious. -- For reasons of making it easier to identify, and repair broken wires later, i would recommend running a Blue, Green, and Yellow wire. Once in the engine bay, run these wires to the Distributor.

Ok .. Distributor wiring. Cut off the Plug from the OLD distributor, because we are going to reuse the Plug, and get ahold of an 8 pin Distributor plug for your NEW OBD1 dist. as well (Harness Side) -- we are going to make a Conversion Harness.

Here is the pinout -- OBD1 Plug >> OBD0 Plug (4Pin)

Orange to Orange
Orange Blue to Orange Blue
White to White
White Blue to White Blue

Simple enough -- Plug it in!

Now, the BLUE/GREEN wire on the OBD 1 side, connect that to the GREEN wire we ran from in the car, and connect the BLUE/YELLOW wire to the BLUE wire we ran from in the car. Simple Pinout form of what i just said is below:

OBD1 Dist Plug >> Wires we ran from in the car

Blue/Green to Green
Blue/Yellow to Blue

Still with me?

On that SAME 8 pin plug that we have made all these connections so far (6 to be exact), there are still 2 wires. Both of these wires will vary in color depending on what car the Distributor came from. I will outline the most common.

*The yellow/green wire is the SAME wire as white. --- white and yellow/green are the SAME thing.

*The black/white wire is the SAME wire as green. --- green and white/black are the SAME thing.

--- Distributors WITHOUT Black/White (green) wire coming out of the Dist, have an INTERNAL coil, and you do not need to run an external coil on your car -- .. your life is made simple. If your Dist has a 7-pin plug instead of the 8 pin, you have an INTERNAL Ignition coil, so disregard the External Coil connection proccess.

OK! ... connect the yellow wire we ran from inside the car, to the yellow/green (or white) wire on the dist.

And finally, (for external coils), run the black/white (or green) wire from the dist, to the NEGATIVE side of your ignition coil.

In Pinout style -- OBD1 plug >> Wires we ran from in the car:

Yellow/Green (white) to Yellow
Black/white (green) to the Negative side of your ignition coil.

........

--There is also a 2 pin plug on the distributor. This plug has a Blue wire, and a Black/yellow wire. Find an original Harness plug, cut it off, and attach it to the blue wire, and black/yellow wire where your original Ignition Coil used to be.

Blue to Blue
Black/yellow to black yellow
-- plug in the Capacitor

Thats all plug it in! Your distributor is NOW wired up, and ready for action.. only a few steps left!

............

This is where it gets tricky. THE ECU!

You CAN, and in fact need, go out and buy a OBD0 to OBD1 conversion harness, don't trust that it is correct!! ... The conversion harness which i was intending to use, actually came out of a running Car, the same exact car for that matter, but i still found that the pinout was incorrect. Fortunately for me, i had a harness which i had made, that had the Stock OBD1 wire colors still intact, and was also pinned out correctly :)

When you buy a harness MAKE SURE that these pins are correct, and going to the appropriate wires -

Plug in your jumper harness and trace back the Orange, Orange/Blue, White, White/Blue, wires on the OBD0 C-plug, and make sure that they correspond to the correct pins on the ECU! The pinout is below:

OBD1 Side:

B11-CYP P CYP(#1 piston position) -P Orange, CYP sensor input, n/a
B12-CYP M CYP -M White, CYP sensor signal, n/a
B13-TDC P TDC(top dead ceter) -P Org/Blue, TDC sensor input, n/a
B14-TDC M TDC -M Wht/Blue, TDC sensor signal, n/a
B15-CKP P CKP(crank position) -P Blu/Green, CKP Sensor input, n/a
B16-CKP M CKP -M Blu/yel, CKP Sensor signal, n/a

-- So, what im saying is - the orange wire from the (OBD0) C-Plug, should go to the pin where the Orange wire should be on the ECU (B11) - If it is NOT --- then REPIN it!! You MUST, if you want the car to start. --- DO the same for the 4 wires i posted above.

Ok! Good! Now ... Do you recall the 3 wires we ran into the car (the 2 sheilded wires, and the other)?

You are going to need to connect the Green wire to Pin B15 (OBD1 harness), and connect the Blue wire to Pin B16 (OBD1) harness ... Again, if you forget to do this, then you are SOL and will be stuck with a NO start situation.

And at last --- the Yellow wire we ran. Connect this wire to pin A21, AND A22 on the OBD1 ECU Plugs.

A21-ICM Yel/Grn, Ignition Control Module output signal, About 10V KOEO
A22-Igniter, same as A21

............

OK .. the firing order, in the case of my conversion, was NOT the same as stock. Like i said, after redrilling the Cam Key, the firing order had been adjusted 90* from stock. After figuring this out, and readjusting the Firing order (by swiching moving the wires), the car started up beautifully.

STOCK firing order (looking at the Dist Cap) is:

1 3
2 4

The MODIFIED Cam Key firing order (while looking at the Cap) is:

2 1
4 3

Keep this in mind for if/when you need to troubleshoot your OBD swap. The best way to see which where Cyl #1 is on your engine after redrilling an d mounting the Distributor is to Take off the Cap, and rotate the Engine to (cyl #1) TDC. Take note of where the Rotor is facing, and that is your new Number one plug on the Cap. The firing order is 1, 3, 4, 2, going CLOCKWISE from that plug.

-----

Well, thats it, Plug in your ecu, and see if your car starts!!

I have NO (helpful) pictures now, but hopefully i will soon. What would you like to have pictures of, what would help you understand what i have written?

TaDa!

http://img.photobucket.com/albums/v650/Messybone/LX-i/DSCF3095.jpg

In the above picture, this vehicles firing order is INCORRECT! Please dont mimic it, your car will not start.

http://img.photobucket.com/albums/v650/Messybone/LX-i/DSCF3097.jpg

http://img.photobucket.com/albums/v650/Messybone/LX-i/DSCF3104.jpg

Re-Chipped his ECU ---

http://home.comcast.net/~ort8ga/ReChip.jpg

rudeludenotmean
10-06-2007, 10:54 AM
OBD1 Dist Pinout is as follows:

Wire Color >> Function:

Orange - CYP P - Cylinder #1 Position Sensor
White - CYP M - "
Orange/Blue - TDC P - Top Dead Center Sensor
White/Blue - TDC - "
Blue/Green - CKP P - Crank Postion Sensor
Blue/Yellow - CKP M - "
Yellow/Green (white) - Igniter Input (from ECU pin A21 & A22)
Black/White (green) - Ignition Coil Output (Ground)(-)

Blue - Tachometer Outout (To Tach/Gauge)
Black/Yellow - Battery Positive (B+, 12V)

LX-incredible
10-06-2007, 11:56 AM
Great info! Now If I could only find a distributor... What ECU did you go with?

thegreatdane
10-06-2007, 12:00 PM
To avoid confusion let me just point out that the firing order itself (1-3-4-2) will still remain the same disregarding any key redrilling. You will just rotate it relative to the cam key rotation.

Not using shielded wires can also not be recommended!

But it's good to see that someone finally writes something about this conversion, good job on that.

rudeludenotmean
10-06-2007, 03:19 PM
Thank you for your input! (edited Original post)

However ... Sheilded wire is "semi" difficult for the average user to come by. The only other GOOD alternative, would be to run a twisted pair of wire for the CKP sensor.

Reason: If one wire receives radio interference, the other wire, who is twisted around the first, will receive the same amount of interference as the wave hits the strands - thus canceling the interference out.

Furthermore -

The CKP system creates its own AC current which is already invulnerable to radio interference, infact, it creates radio interference, which is why its shielded when ran in the wire loom; to reduce interference in the OTHER wires.

If you run a a seperate line, outside of the wire loom, as you will need to, sheilding of the wire is not as neccessary (if at all) because there are no other wires close enough to it that need protecting.

Again, the shielded wires are not THAT serious.

(the Original post has been modified to reflect this)

EricW
10-06-2007, 05:00 PM
Thats Just the meat of the conversion, you still have to repin a conversion harness to get every thing else to work. e.g. map sensor, oxygen sensor(s), TPS, check engine light, injectors, purge soleniod, and several other things

rudeludenotmean
10-06-2007, 05:05 PM
I didnt ...

I had made a conversion harness for a EF to OBD1, and the only re-pinning that needed to be done from the harness i built was for the CYP and CKP, and TDC. No other repinning was neccessary.

If you buy a OBD0 to OBD1 88-91 Civic harness, those should be the only pins needed to be changed around, as outlined in the original post:

"Plug in your jumper harness and trace back the Orange, Orange/Blue, White, White/Blue, wires on the OBD0 C-plug, and make sure that they correspond to the correct pins on the ECU! The pinout is below:

OBD1 Side:

B11-CYP P CYP(#1 piston position) -P Orange, CYP sensor input, n/a
B12-CYP M CYP -M White, CYP sensor signal, n/a
B13-TDC P TDC(top dead ceter) -P Org/Blue, TDC sensor input, n/a
B14-TDC M TDC -M Wht/Blue, TDC sensor signal, n/a
B15-CKP P CKP(crank position) -P Blu/Green, CKP Sensor input, n/a
B16-CKP M CKP -M Blu/yel, CKP Sensor signal, n/a

-- So, what im saying is - the orange wire from the (OBD0) C-Plug, should go to the pin where the Orange wire should be on the ECU (B11) - If it is NOT --- then REPIN it!! You MUST, if you want the car to start. --- DO the same for the 4 wires i posted above."

---- But ----

The car has a known CEL for O2 Heater circuit; didnt pull the code, but i know thats why its on.

Your saying that the other sensors are incorrectly pinned as well? It really doesnt make much sense, seeing as how the car is running fine, and the ECU is NOT in limp mode. CEL Does its thing on initial Key turn like its supposed to, no CEL's until startup ... Heated O2.

However, because of what you have written, i will verify the pins, again ... ... ... ... I really dont think its wrong, however. The car would have extreme drivability problems if major sensors like the Map sensor, TPS, Oxy, and INJECTORS were pinned wrong on the harness.

EricW
10-06-2007, 05:23 PM
I don't remember how much work I had to do to repin but i'm just saying that they need to be verified before the ecu is plugged in that way you don't fry something in the ecu or other parts. I might have just done more work on my harness since I tried to retain all of the stock wiring and use old/spare/unused for the OBD1 wires for the new wires. But its easier for you to say what exactly needs to be done since you've done it recently. I know i removed 8 to 10 wires from my conversion harness since they where not used.

rudeludenotmean
10-06-2007, 05:32 PM
There ARE several wires on the harness which are not used (the conversion harness), but they will not effect ANYTHING in the ECU if they are left on the conversion harness. Same goes for the unused wires on the Chassis side ... nothing will be affected.

Besides that, its MY ECU hes running now :) so .. if it frys its my fault, haha.

I've retained the original harness, Ran 3 wires, and actually pinned into the OBD0 harness for a COMPLETELY stock look :) Gotta love it .. when we update with pics .. that will tell all.

There are ZERO drivability issues with the car. i'm certain that nothing else must be repinned, but i always welcome criticism if it will benefit this guide.

ghettogeddy
10-06-2007, 07:38 PM
ha rudelude so ur up to build me one when my motor is out the shop right lol
oh and it was nice meting u and ill have the pics of the harness up soon

bobafett
10-06-2007, 08:03 PM
cool info, thanks for the great post!

rudeludenotmean
10-07-2007, 04:28 PM
ha rudelude so ur up to build me one when my motor is out the shop right lol
oh and it was nice meting u and ill have the pics of the harness up soon

I'm up to repining the harness that your gonna buy after your build is done ... haha

ghettogeddy
10-07-2007, 04:48 PM
I'm up to repining the harness that your gonna buy after your build is done ... haha

lol
ight ill let u know
i might as well go ahead and do it while i do my fi swap then all the harness can be tied together lol just gona have to find someone to do the key re drill and tap welding lol

rudeludenotmean
10-07-2007, 05:02 PM
Well, you might have figured out i'm always down for a challenge ... lemme know what you want to do.

Then next Accord conversion I do shouldn't take more than 3 hours now that I've done it. .... Not including Dist work .. haaha

coope
10-07-2007, 05:44 PM
how is ur car running is it better that way and u should make a conversion harness i'll buy

EricW
10-07-2007, 05:47 PM
lol
ight ill let u know
i might as well go ahead and do it while i do my fi swap then all the harness can be tied together lol just gona have to find someone to do the key re drill and tap welding lol

I would run with the FI swap for at least a week before you do the OBD1 swap that way you know that there are no "bugs" with the FI swap.

ghettogeddy
10-07-2007, 05:53 PM
I would run with the FI swap for at least a week before you do the OBD1 swap that way you know that there are no "bugs" with the FI swap.

well im not swaping it onto a carb motor im doing a full fi motor buying everything brand new lol minus i few hard to get parts like ecu and such lol

rudeludenotmean
10-07-2007, 06:36 PM
Why not do it all at once? I really dont see a benefit from swaping to MPFI and THEN switching to OBD1 ...

Its all the same .. do it all at once.

MessyHonda
10-08-2007, 12:23 AM
how is ur car running is it better that way and u should make a conversion harness i'll buy




i still need to get it tuned. but overall it runs fine...no more 6850 redline....its 7200 now...i spiked it a lil bit since i got headers installed also and it reves up way quicker. this swap is not for beginners...and it wont do you any good if you dont have supporting mods. my next swap is stage 2 cam and blox intake manifold so i can get rid of EGR...and it will just look cleaner. my numbers should be around 120-130whp

BITESIZE
10-08-2007, 12:23 AM
What are the advantages to this?

ghettogeddy
10-08-2007, 12:29 AM
What are the advantages to this?

being able to tune the ecu to your specs so things like fuel air flow
u can use a wide ban to help tune as well

MessyHonda
10-08-2007, 12:30 AM
What are the advantages to this?



:huh:


i just did it so i can get rid of my black box as a former dx owner i never want to see another vac line in my car. the performance view is that now you wont have vacuum advance on the distributor making it electronic....you have more control over the engine...especially if you have serious investment and dont want to blow it up racing or anything. it works as a charm....feels like a high end car since the engine is soo soft and quiet now.

BITESIZE
10-08-2007, 12:31 AM
I know it is useful for turboing, but I never have spent time to look into this.

rudeludenotmean
10-08-2007, 01:05 AM
Tuning an N/A car is just as useful as tuning a boosted one. Both cars will see gains, in the same, and different ways.

guaynabo89
10-08-2007, 08:27 AM
lol

I remember when I first swapped to obd1 on my hatch. After I took it out for a test drive it felt as i had just given the car a good tune up. Accel was smoothed out and the 7000 rpm redline of the p75 was nice too.

2drSE-i
10-08-2007, 12:49 PM
our vacuum advance distributor blows balls. I cant wait to get my obd-1 swap underway.

TWOLOUDNPROUD
10-08-2007, 07:19 PM
our vacuum advance distributor blows balls. I cant wait to get my obd-1 swap underway.

Aman:bow:

rudeludenotmean
10-09-2007, 12:31 AM
our vacuum advance distributor blows balls. I cant wait to get my obd-1 swap underway.

On with it already.

2drSE-i
10-09-2007, 08:44 AM
On with it already.

when i get a new daily driver i will. For now im happy talking shit about honda engineers

coope
10-09-2007, 11:51 AM
i would but it really sounds to hard if sum one make me one dis. and harness i will buy.. and everything i need to go along with it .

2drSE-i
10-09-2007, 11:58 AM
if this sounds too hard then i wouldnt even bother coope. Even with a harness, perfectly working distributor, and all other parts it still takes an excessive amount of know-how.

bobafett
10-09-2007, 12:03 PM
and i doubt you will ever find anybody to build an entire kit to swap this. just too much work is involved, and its not HARD stuff, its just a pain, and unlikely that anybody would like the price on a turnkey setup. :)

rudeludenotmean
10-09-2007, 12:09 PM
What do you want to pay for such a kit? I've got nothing but time on my hands to build a kit for someone .. woo hoo ..

A deposit would need to be paid, for parts, up front.. but I could do it.

rudeludenotmean
10-09-2007, 01:29 PM
ReChipped Mess's ECU yesterday -

http://home.comcast.net/~ort8ga/ReChip.jpg

EricW
10-09-2007, 06:37 PM
pic doesn't work :redx:

bobafett
10-09-2007, 06:40 PM
rudeludenotmean i don't know where you came from (pp?) but you are pretty damn productive hahah! :)

rudeludenotmean
10-09-2007, 09:29 PM
Actually ... I really don't get on forums much anymore. I'm here because I told Jesse I wanted to make a "definitive" guide for people planning on doing this conversion themselves in the future.

After running into a couple of problems on his conversion -which should have never been there -hella weren't my fault, i told him that I would document the conversion completely here.

That my back story. haha .. I'm actually quite proficient with modifying Honda's (Acura :P) ... It's what I do --

I guess, when it comes down to it, I'm originally from Hondaswap, and then PreludePower, and then, now, here.

And ... I have no Red X's on the pictures :)

MessyHonda
10-10-2007, 12:00 AM
ReChipped Mess's ECU yesterday -

http://home.comcast.net/~ort8ga/ReChip.jpg



nice...good thing i joined prelude power cuz that was how i got to meet you.

2drSE-i
10-10-2007, 08:01 AM
What do you want to pay for such a kit? I've got nothing but time on my hands to build a kit for someone .. woo hoo ..

A deposit would need to be paid, for parts, up front.. but I could do it.


for simplicities sake i would definatley buy a harness from you, if you were willing to repin it and everything. id probly pay like 175 for it...

coope
10-10-2007, 02:27 PM
i'll pay 200 for a kit and how does ur car run with that ecu i got someone to install the harness for me so thats no worry

bobafett
10-10-2007, 03:46 PM
awesome... well its nice to have you on the site helping us out :)

rudeludenotmean
10-11-2007, 10:38 AM
Its AOK --

Umm ... Can someone use this guide, and let me know if you find any flaws? ...

gigabytedragon
10-22-2007, 04:51 PM
hey rudeludenotmean a couple of posts back you said to use a harness for a 88-91 civic, would that be Si or DX

deevergote
10-24-2007, 05:36 PM
Did you adjust the writeup to cover the wiring that's taken care of with the Civic conversion harness? Or is that still needed to follow your directions? I'm just looking at this now... I need to pull my stuff apart to really understand it! I have a 92 Accord dizzy in my basement, so I'm going to do this conversion.

Any pics of how you modified the tabs and cam key? I know you said it's application dependent, but it'd still be helpful to get an idea!


Also, what ECU was used? I'm a 4th gen guy, and we usually use chipped Civic ECUs... P06 for the non-VTEC engines, and P28 for the VTEC engines. What did you use for tuning, and how did you get started (basemap?)

Sorry if this was all covered... this is all so foreign to me that I don't know where to look for the answers! (weird... just one generation older than what I know, and it might as well be a Citroen!)

EricW
10-24-2007, 07:12 PM
Did you adjust the writeup to cover the wiring that's taken care of with the Civic conversion harness? Or is that still needed to follow your directions? I'm just looking at this now... I need to pull my stuff apart to really understand it! I have a 92 Accord dizzy in my basement, so I'm going to do this conversion.

Any pics of how you modified the tabs and cam key? I know you said it's application dependent, but it'd still be helpful to get an idea!


Also, what ECU was used? I'm a 4th gen guy, and we usually use chipped Civic ECUs... P06 for the non-VTEC engines, and P28 for the VTEC engines. What did you use for tuning, and how did you get started (basemap?)

Sorry if this was all covered... this is all so foreign to me that I don't know where to look for the answers! (weird... just one generation older than what I know, and it might as well be a Citroen!)


The P75 base map works best. I would either run an unchipped P75 or another ecu(V-tec or non V-tec) that is chipped and running the P75 base map.

deevergote
10-25-2007, 06:24 AM
Cool, thanks! That's the Integra LS ECU, right?

If I can find a P75 basemap, I'll probably just use a p06. They're quite easy to find.

EricW
10-25-2007, 09:30 AM
Cool, thanks! That's the Integra LS ECU, right?

If I can find a P75 basemap, I'll probably just use a p06. They're quite easy to find.

Yes, that sounds right.

stat1K
10-31-2007, 12:02 PM
i was wondering if the p06 would work also because i happened to find a great deal on a p06 and a pg7 from a guy on my local forum and i'm wondering since it's non-vtec sohc if it might work better? i know they're easy and cheap to chip i guess just get the p75 fuel map and do that since i can't seem to find one for lx-incredible. i did find an obd1 pr4 i guess it's supposed to be similar to the p75 but i would like some clarification on this too.

guaynabo89
10-31-2007, 12:14 PM
yeah it will work . if your ultimate goal is to chip n tune then you shouldn't have a problem.

even a vtec ecu should work. It might not run to nice since it will richen the top end etc.

I don't know about the PR4 ecu though. Did around pgmfi.org . I think there are ecus that are more preferable than others

MessyHonda
10-31-2007, 12:28 PM
I ran a PR4(integra v-tec) it ran alright on my car but the tach would jump crazy after like 4-5k rpm. i was getting like 25mpg with a heavy foot... Right now im running a P06 that has been tuned to my car with my 280 cam.

STAGE 2 - PRIM INT 280° .392 LIFT
SEC INT 268° .383 LIFT
EX 288° .394 LIFT
Recommended for carburetor engine. However, it will work on F.I. with a noticeable idle
and possibly a slight surge. Strong mid range. No mods are required

my engine does surge alot when its cold so i have to let it warm up...but other than that its alright now just to finish my swap i need to get a vss signal to the ecu...i have a spare cluster to tinker with.

2drSE-i
10-31-2007, 01:46 PM
if you could combine p06 timing with p75 fuel i think it would work pretty well. But it doesnt really matter if your running Crome Pro with autocorrect :-)

stat1K
11-01-2007, 09:46 AM
rofl well obviously not but hmm so maybe this p06 will be of some use afterall.

guaynabo89
11-06-2007, 07:56 AM
I was looking thrugh my pictures and found this diagram I had made for ericw to try and troubleshoot a problem he was having. Its basicly a quick diagram of the wiring for the obd1 distributor when wired into the accord harness.


http://img.photobucket.com/albums/v499/sinnedone/obd1distdiagram.jpg





Rudelude Please compare to your notes and if evrything is ok you can add it to your original post.






These next couple of pictures are for the vss issue. If you do not get a cel dont worry about it. but if you do you must use the speed pulser output from behind the gauge cluster to the ecu vss input. You must use the speed pulser instead of the stock accord vss signal. Once you swap the speed pulser output to the vss wire behind the gauge sluster you must get a 6k resistor to wire in to get the correct polarity vss signal.


Anyway heres a couple of pics that will ease the install.







http://img.photobucket.com/albums/v499/sinnedone/vss.jpg







http://img.photobucket.com/albums/v499/sinnedone/DSC000171.jpg

MoonScryer
11-21-2007, 05:26 AM
Did anyone ever figure out if a EF Civic DX or Si conversion harness was used? They are both a bit different.

I'm going to guess the Si.

SQ is the SQUAD
01-28-2008, 02:16 PM
there is no dx conversion harness per say. they are all for mpfi (si) if you have a dx, you have to convert to mpfi first (4 injectors) then use the conversion harness. you can get the harness for cheap off ebay, like $50 but the connectores that go into the ecu are real cheap and chew up easly. if you dont plan on removing your ecu alot they will be fine. or you can always depin it and put on the factory connectors you cut out of another car.


on a side not, anyone who needs a modified obd1 ecu hit me up, i got them by the boatloads, chipping them daily

SephirXV
05-17-2008, 03:06 PM
I have a question about the "redrilling cam key alters your fire order" (or at least the order the plug wires go onto the dizzy).

It's my understanding that when you redrill the key, it lines up so that distributor points to cable 1 while the engine is at #1 TDC. If the dizzy's rotor still spins the same direction, and starts out at the same spot, how can the other 3 cylinders not also be in line?

I plan to take my dizzy and stake the base next to the shaft that holds the cam key, at the existing holes in the key, which basically marks where the pin should be when the the engine is at #1 TDC. Then, mount the dizzy, turn the engine until it's at #1 TDC, pull the dizzy out, and stake the key next to the two stakes I made before. The stakes on the key represent where the pin that holds the key on should be at #1 TDC, and when the key is mounted with the pin at that position, distributor and engine should hit cylinders at the same time, plus or minus a few degrees to adjust for by rotating the dizzy a little bit.

If there is something wrong with this line of reasoning, would someone please point it out and explain to me how I'm wrong?

2drSE-i
05-17-2008, 09:25 PM
the 4th gens firing order is different than ours. Thats why you have to get the cam key redrilled.

EricW
05-20-2008, 04:03 PM
The firing order isn't different. You just can't mount the 4th gen distributor in its TDC position on the A20 with out interference issues. That is why the cam key must be re-drilled. So that TDC on the motor matches TDC on the distributor in its mounted position.

SephirXV
05-20-2008, 07:37 PM
Concerning guaynabo89's diagram above, I have a quick question about the cable that goes from our distributor to the left plug on the coil. That particular stretch carries the two wires that go on the small plug in the new dizzy, the blue tach wire and the black/yellow coil positive. It also carries a third wire, which I'm not sure of and didn't have my manual with me to see what it is.
This third wire is all black I believe, and connected to the casing of our old dizzy unshielded, as if it were a ground. However, following the other end, it goes past the coil, through the radio condenser (fancy square capacitor) and then dives underneath the fusebox.
Generally anything coming from the fusebox is positive (you can get ground almost anywhere in a car), but it appears to ground the dizzy. My final answer (in the form of a question) is does this wire represent any of the wires in the diagram, and if so, which one? I'm hoping for the green coil negative.

SephirXV
05-20-2008, 08:08 PM
The firing order isn't different. You just can't mount the 4th gen distributor in its TDC position on the A20 with out interference issues. That is why the cam key must be re-drilled. So that TDC on the motor matches TDC on the distributor in its mounted position.

I thought that sounded weird. A) I've been told all hondas in this class fire 1342, and B)if swapping the wires fixed it, what if someone's rotation wasn't anywhere near 90 degrees (or multiple thereof). I guess all will be settled when I get my key back from the drill press.
Speaking of which, does someone know offhand, on the stock dizzy, when at #1 TDC, which piston is the rotor pointing at? I know our timing is supposed to 25-15 (I'm guessing, I could be 10 - 20 off) degrees BTDC, but that's not the same piston?! We want to fire near BDC (not BTDC, bottom dead center), surely time from spark to peak ignition pressure isn't over 90 degrees?!

I'd like to think everyone who pitches into to these documents, especially with the pretty Paint/Gimp diagrams.

EricW
05-20-2008, 08:57 PM
Concerning guaynabo89's diagram above, I have a quick question about the cable that goes from our distributor to the left plug on the coil. That particular stretch carries the two wires that go on the small plug in the new dizzy, the blue tach wire and the black/yellow coil positive. It also carries a third wire, which I'm not sure of and didn't have my manual with me to see what it is.
This third wire is all black I believe, and connected to the casing of our old dizzy unshielded, as if it were a ground. However, following the other end, it goes past the coil, through the radio condenser (fancy square capacitor) and then dives underneath the fusebox.
Generally anything coming from the fusebox is positive (you can get ground almost anywhere in a car), but it appears to ground the dizzy. My final answer (in the form of a question) is does this wire represent any of the wires in the diagram, and if so, which one? I'm hoping for the green coil negative.

Since I no longer have radio condenser, and I didn't go look at the car, I'm looking at the diagram in the Honda manual. The negative wire for the radio noise condenser attaches to a screw on the ignitor for a ground and the positive side connects to the black/yellow wire(s). The radio noise condenser/wires are not used in the OBD1 swap. If i remember right the obd1 ignitor has one built in.

The black/yellow wires attach to the coil positive and the green wire from the ignitor in the distributor is the negative coil wire.


I'll go look at the car later to verify all of this but it may be hard since I'm not running the stock ignitor either since I'm using the msd system and used an ignitor bypass which I built.

'A20A3'
05-21-2008, 07:06 PM
im too lazy someone make me a kit i'll buy it haha sold :pc: wiring makes me angry, replacing stuff works better for me.

SephirXV
05-22-2008, 07:42 AM
Coil Diagram (http://picasaweb.google.com/SephirXV/Misc/photo?authkey=hdrhuq6q6wg#5203224997823743890)

Terminal A comes from the ignition switch (positive), so I assume that "Coil Negative" is terminal D?
And then I suppose terminal C is coil positive?

SephirXV
05-22-2008, 11:48 AM
The car has a known CEL for O2 Heater circuit; didnt pull the code, but i know thats why its on.

Is the heater circuit on your 4-wire o2 sensor bad, or did you hook up to one of the existing 1-wire sensors?

AccordB20A
08-07-2008, 02:06 AM
quick question? is a p27 chipable??

and i have Searched the web but cant find.. a list of ALL honda ECUs OBD number and whether they are chipable

89T
08-18-2008, 06:10 PM
chipable ecu's
USDM, EDM, or JDM
Non-VTEC
P05
P06
P09
P1K
P27
P29
P54
P74
P75
PR4
VTEC ECUs
P08
P28
P30
P61
P70
P72
P91
PR3

elpuma
02-18-2012, 11:25 PM
I guess its easy. I used Boomslang MPFI OBD0 to OBD1 conversion harness.
I used this pinout to double check everything on it http://carotman.no-ip.com:8888/personal_site/tech/ecu_pinouts/1989A20A3pinout.html

then i came up with this


OBD1->OBD0 - Function
A01 ->A01 - #1 injector
A02 ->A07 - #4 injector
A03 ->A03 - #2 injector
A04 ->N/C - VTEC solenoid Valve
A05 ->A05 - #3 injector
A06 ->N/C - O2 Sensor Heater Control
A07 ->A6&A12 - Fuel Pump Relay (FLR1)
^^boomslang A07 ->A12&14
A08 ->N/C - Fuel Pump Relay (FLR2)
A09 ->A11 - EACV
A10 ->N/C - EGR solenoid valve
A11 ->N/C -
A12 ->N/C -
A13 ->B06 - Check Engine Light (MIL)
A14 ->N/C -
A15 ->B01 - A/C Clutch Relay
^^boomslang A15 –>B02
A16 ->N/C -
A17 ->N/C -
A18 ->N/C -
A19 ->N/C -
A20 ->B02 - Purge Control Solenoid Valve
^^boomslang A20 ->A06
A21 -> run a wire to dizzy - Igniter Power Source (IGP1)
^^boomslang A21 ->15&17
A22 ->N/C - Igniter Power Source (IGP2)
A23 ->A02 - Power Ground (PG1)
A24 ->A04 - Power Ground (PG2)
A25 ->A13 - Main Relay IGP1 (IG Power)
A26 ->A18 - Logic Ground (LG1)
A27 ->N/C -
B01 ->A15 - Power Source (IGP2)
B02 ->A16 - Logic Ground (LG2)
B03 ->N/C -
B04 ->N/C - Service Check Connector
B05 ->B08 - A/C Switch (ACS)
B06 ->N/C -
B07 ->N/C -
B08 ->N/C - P/S Pressure Switch
B09 ->B13 - Starter Switch Signal (STS)
B10 ->B18 - Speed Sensor
^^boomslang B10 ->B16
B11 ->C01 - CYL Sensor
^^boomslang B11 ->B08
B12 ->C02 - CYL Sensor
^^boomslang B12 ->B10
B13 ->C03 - TDC Sensor
B14 ->C04 - TDC Sensor
B15 ->run shielded wire to dizzy- Crank Angle Sensor
^^boomslang B15 ->C01
B16 ->run a shielded wire to dizzy- Crank Sensor
^^boomslang B16 ->C02
D01 ->A17 - Back Up Fuse
^^boomslang D01 ->B01
D02 ->N/C - Brake Switch
D03 ->N/C - Knock Sensor
D04 ->N/C- Service Check & Ignition Timing Connector (SCS)
D05 ->N/C -
D06 ->N/C - VTEC Pressure Switch
D07 ->N/C - Data Link Connector
D08 ->N/C -
D09 ->B14 - Alternator
D10 ->B19 -
D11 ->C07 - Throttle Position Sensor (TPS)
D12 ->N/C -
D13 ->C06 - TW Sensor
D14 ->C16 - O2 Sensor
^^boomslang doesn't run this connection but they provide wires to use an obd1 o2 sensor
D15 ->C05 - Intake Air Temperature Sensor
D16 ->N/C -
D17 ->C11 - MAP Sensor
D18 ->N/C -
D19 ->C15 - Sensor Voltage (VCC1)
D20 ->C13 - Sensor Voltage (VCC2)
D21 ->C14 - Sensor Ground (SG1)
D22 ->C12 - Sensor Ground (SG2)

The pinouts in bold are the ones you have to rearrange. Underneath them in bold i show how boomslang ran them which is wrong and needs to be arranged like the top one.

Tdurr
03-13-2012, 07:10 PM
http://technet.ff-squad.com/wiring.obd1.htm

Obd1 harness/ecu pinout to double check your wires.

Accord obd0 pinout

http://carotman.no-ip.com:8888/personal_site/tech/ecu_pinouts/1989A20A3pinout.html


Something I thought should be added to the first post to help.

A20A1
05-15-2012, 12:12 AM
Would SCSI cables be an option if you wanted to make custom ecu connections? I have a few old printer ones laying around, and they are about 4' to 6' long.

SQ is the SQUAD
06-03-2014, 09:29 AM
what gauge wires should be used for the 3 you have to add. crank position(2) and ignitor.

can all 3 be ran in a strand shielded together, or should the 2 crank wires be shielded and the 3rd be separate?

obd0driver
06-03-2014, 09:47 AM
Better safe them sorry I would say shield them. As far as size go's they use a 16g or 18g stock I think. So I wouldn't go bigger then 14g I think that would be over kill.

Sent from my SPH-L720 using Tapatalk

Tdurr
06-04-2014, 09:30 PM
For my shielded wire I went to lowes, got the 4wire shielded bundle, and used that. I think its like 16g wire.

EricW
06-05-2014, 08:29 PM
For my shielded wire I went to lowes, got the 4wire shielded bundle, and used that. I think its like 16g wire.

Same thing I did.

Sent from my MB860 using Tapatalk 2

Shane86
06-21-2017, 03:26 PM
This is for Code 17 or VSS signal.don't know if it works for everybody but it worked for me on my 86. I swap the little white box from a 89 cluster to my 86 cluster.the only difference between the little boxes was the 89 has one single wire coming off of it that the 86 did not have. I give the credit to Rendon L-xi

Shane86
05-24-2018, 07:07 PM
A closer look at the Distributor wiring. Left side is A21 B15 and B16 will be your shielded wire.the green wire under A21 is for external coil distributor only. And the four wires on the right side of the connector you just match the four colors up