Darn PGM-FI light problem oh noess..

[pablo3264]

The light use to come on id say 2-3 times a month mostly while idling for long periods of time, thought the problem went away after changing out my old fuel injectors which were totally fucked, the rubber on the tips of the injectors didnt even feel like rubber anymore they were hard ass rock and some actually broke apart from trying to bend them also some o rings were cracked on the injector itself but anyway put in the new injectors, car seemed fine and gained some power since some of the other old injectors were totally fucked i have pics of them if someone might wanna see lol looks like they havent been changed since 86...

Well no pgm-fi light for awhile then my catalytic converter started making noise about a week ago not sure and sounded like it was clogged and made my exhaust a little louder than usual, so gonna install the new one im about to get tomorrow on thursday. Now the light comes on alot more than usual id say once every 2 days sometimes more and when it does come on its when im driving only, not idling like in the past. Also when it comes on and I come to a stop i have a hunting idle (rpms go up and down). Checked the light under the ash tray its always been blinking since ive had the car, not sure how to count the blinks it never stops?

Could this PGM-FI light issue be related to my cat going bad since it started acting up alot more at the same time as my Cat started going bad?

Sorry for the long write up, just wanted to be detailed as i could lol and i always seem to post late at night or should i say early early morning haha

[cygnus x-1]

There are no sensors after the cat (like on newer cars) so the computer won't know anything about it's condition. It's possible though that the O2 sensor is going bad, causing the engine to run rich and clog up the cat.

You really need to figure out what the diagnostic code is though. Between the blinks there should be some longer and shorter pauses. That's how you would interpret the numbers.

You can download the service manual (pdf format) from here:

http://bluegreenlabs.com/Prelude/Svc...l%20Manual.pdf

It will help you figure out the code and tons of other stuff too.


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[pablo3264]

There are no sensors after the cat (like on newer cars) so the computer won't know anything about it's condition. It's possible though that the O2 sensor is going bad, causing the engine to run rich and clog up the cat.

You really need to figure out what the diagnostic code is though. Between the blinks there should be some longer and shorter pauses. That's how you would interpret the numbers.

You can download the service manual (pdf format) from here:

http://bluegreenlabs.com/Prelude/Svc...l%20Manual.pdf

It will help you figure out the code and tons of other stuff too.


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Ill look for a pause today, the darn pdf wont load up for me lol its stuck at the loading screen.

And where is the 02 sensor on my 86 si i cant find info on the Haynes repair manual lol searched it up and saw some say it was on the intake manifold not sure myself

[cygnus x-1]

Ill look for a pause today, the darn pdf wont load up for me lol its stuck at the loading screen.

And where is the 02 sensor on my 86 si i cant find info on the Haynes repair manual lol searched it up and saw some say it was on the intake manifold not sure myself

I forgot to mention, that manual is huge; like 90Mb. So it will take awhile to download. I recommend saving it to a file first, then opening it after it's finished downloading.

The O2 sensor is screwed into exhaust manifold right above where the single exhaust pipe going downward joins to it. It's a round thing about 2 inches long with a wire coming out of it.


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[pablo3264]

I forgot to mention, that manual is huge; like 90Mb. So it will take awhile to download. I recommend saving it to a file first, then opening it after it's finished downloading.

The O2 sensor is screwed into exhaust manifold right above where the single exhaust pipe going downward joins to it. It's a round thing about 2 inches long with a wire coming out of it.


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Just saw the light blink 12 times with a pause so its EGR related, so first thing is i would need to clean the egr with carbon cleaner or replace it? Could some passages be clogged with carbon leading to it also?

[cygnus x-1]

Just saw the light blink 12 times with a pause so its EGR related, so first thing is i would need to clean the egr with carbon cleaner or replace it? Could some passages be clogged with carbon leading to it also?

Oh yeah, those things get clogged up after awhile. Take it off to give it a good cleaning and make sure the diaphragm moves ok. Check the wiring harness for corroded or broken wires and contacts.

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[pablo3264]

Oh yeah, those things get clogged up after awhile. Take it off to give it a good cleaning and make sure the diaphragm moves ok. Check the wiring harness for corroded or broken wires and contacts.

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Im gonna pick up my oxygen sensor i ordered from oreilly in a little bit but where exactly is the Egr located i dont know how it looks is it covered by something?

Gonna buy some carb clean to clean it out, just want to get this cleaned today and install the new cat and o2 sensor so i can rid myself of these problems finally

[pablo3264]

Oh yeah, those things get clogged up after awhile. Take it off to give it a good cleaning and make sure the diaphragm moves ok. Check the wiring harness for corroded or broken wires and contacts.

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Nvm found how it looks from the pdf manual u posted, great manual the Haynes seems more complicated to me I just hate how its a hassle to scroll through it all lol otherwise im thankful for it really helps thanks man

[cygnus x-1]

Nvm found how it looks from the pdf manual u posted, great manual the Haynes seems more complicated to me I just hate how its a hassle to scroll through it all lol otherwise im thankful for it really helps thanks man

The pdf version isn't as easy to navigate as a printed copy, but the price is right. I have the Haynes and Chiltons manuals too. They suck compared to the factory manual.

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[pablo3264]

The pdf version isn't as easy to navigate as a printed copy, but the price is right. I have the Haynes and Chiltons manuals too. They suck compared to the factory manual.

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Agreed.

Bolted up the new cat, old cat didnt look clogged as it sounded, had to cut 1 bolt off since it was so messed up, new cat sounds great, gonna do the 02 sensor today didnt have anymore light yesterday and besides its a pain to get to it since there like no room for your hand and a wrench lol I know theres 02 sockets but which one would be the right one to get it make my job a hell of a lot easier??

[cygnus x-1]

Agreed.

Bolted up the new cat, old cat didnt look clogged as it sounded, had to cut 1 bolt off since it was so messed up, new cat sounds great, gonna do the 02 sensor today didnt have anymore light yesterday and besides its a pain to get to it since there like no room for your hand and a wrench lol I know theres 02 sockets but which one would be the right one to get it make my job a hell of a lot easier??

I have one of the offset type O2 sockets, like this:

http://www.amazon.com/Great-Neck-252...091997&sr=1-12


Seems to work ok. Usually you can rent special tools like that from Autozone, and I think it might even be free (leave a deposit and get it back when you return the tool).


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[pablo3264]

I have one of the offset type O2 sockets, like this:

http://www.amazon.com/Great-Neck-252...091997&sr=1-12


Seems to work ok. Usually you can rent special tools like that from Autozone, and I think it might even be free (leave a deposit and get it back when you return the tool).


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Yeah they charged 26 for a deposit, everything worked out ok, but how the heck do i get the bolts off the egr theres like no room for my hand or a wrench even with extensions lol

[cygnus x-1]

Yeah they charged 26 for a deposit, everything worked out ok, but how the heck do i get the bolts off the egr theres like no room for my hand or a wrench even with extensions lol

You may have to remove other stuff to get to it; or use a u-joint/wobble socket.


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[pablo3264]

You may have to remove other stuff to get to it; or use a u-joint/wobble socket.


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Cleaned the egr about 2 hours ago and disconnected my battery to reset the ecu and installed the egr and hooked the battery back up and the dam light came back on after like 10min of driving which sucks

What else could be the problem?

[pablo3264]

Cleaned the egr about 2 hours ago and disconnected my battery to reset the ecu and installed the egr and hooked the battery back up and the dam light came back on after like 10min of driving which sucks

What else could be the problem?

Im thinkin maybe a relay? read alot and found old threads about this same problem... Or it could well be the lift sensor inside the egr which id have to get a new one, goodbye $150 :'(

[cygnus x-1]

Have you checked to see if the EGR valve is actually opening? There are a number of possibilities here. I think there is a troubleshooting chart in the manual. Check in the PGMFI emissions controls section.

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[Dr_Snooz]

There is a troubleshooting procedure in the manual and possibilities for failure range from bad sensors to bad solenoids to bad vacuum lines to bad wires to a bad EGR valve to a bad ECU. It's well worth the time and effort to do the troubleshooting. The troubleshooting sequence does require a PGM-FI test harness at some point, but you will probably find the problem before then.

[pickupman6]

First thing to check would be vacuum at the egr. Pull the hose off egr, I believe it is #16. Place your finger over the hole. There should be no vacuum. Next find hose #17. Pinch it off. You should have vacuum on 16 now. If you do plug 16 back in and pinch 17. The car should stall. If it doesn't pull the lift sensor off of the egr valve by unclipping the 2 wire clips. Check to make sure the plunger moves freely on the sensor. Take a piece of packing tape and place it over the egr hole where the sensor was and pinch 17 again. You should be able to see the diaphram in the egr move and the car should stall. If you have a vacuum pump pull vacuum on the valve and make sure it holds. You can also do this with your mouth and tounge. If it doesn't hold vacuum the valve is bad if it does take the tape back off and pull the oring gasket out of the lift sensor and apply a bead of 3M yellow weather stripping adhesive and gasket maker in the groove put the oring back in place and install the lift sensor. I have had 4 egr valves leaking from the lift sensor gasket, and as far as I know you can't buy just the sensor or gasket. Hope this solves it for you if not I have more to try

[ecogabriel]

My 0.02 below,

There is a troubleshooting procedure in the manual and possibilities for failure range from bad sensors to bad solenoids to bad vacuum lines to bad wires to a bad EGR valve to a bad ECU. It's well worth the time and effort to do the troubleshooting. The troubleshooting sequence does require a PGM-FI test harness at some point, but you will probably find the problem before then.

You only need a vacuum pump and a multimeter; I posted something on how to test the EGR valve. Very briefly, get multimeter in continuity scale (10-20kohms should be fine) and put one probe in the CENTER contact in the valve's connector and the other probe to one of the outer contacts. With a vaccum hose attached, apply some vacuum and see how the readings in the meter change. Repeat on the other outer contact; one side will show increased numbers with increased vacuum while the other will see decreased values.
Go slowly with the vacuum so you can see how the numbers change or if there is any discountinuity. If one side does not change at all, or there is a discontinuity, the EGR sensor is defective.

I have tried this to diagnose my own EGR fault code and to pick up WORKING EGR valves from the junkyard. I even have a spare valve laying around somewhere, and a working solenoid...

First thing to check would be vacuum at the egr. Pull the hose off egr, I believe it is #16. Place your finger over the hole. There should be no vacuum. Next find hose #17. Pinch it off. You should have vacuum on 16 now. If you do plug 16 back in and pinch 17. The car should stall. If it doesn't pull the lift sensor off of the egr valve by unclipping the 2 wire clips. Check to make sure the plunger moves freely on the sensor. Take a piece of packing tape and place it over the egr hole where the sensor was and pinch 17 again. You should be able to see the diaphram in the egr move and the car should stall. If you have a vacuum pump pull vacuum on the valve and make sure it holds. You can also do this with your mouth and tounge. If it doesn't hold vacuum the valve is bad if it does take the tape back off and pull the oring gasket out of the lift sensor and apply a bead of 3M yellow weather stripping adhesive and gasket maker in the groove put the oring back in place and install the lift sensor. I have had 4 egr valves leaking from the lift sensor gasket, and as far as I know you can't buy just the sensor or gasket. Hope this solves it for you if not I have more to try

Last test would be disconnect the EGR solenoid wires and energize it directly from the battery. you should hear the solenoid click and, if doing it with the engine running, it should stall almost immediately.

If you have a vacuum gauge (or vacuum pump) you can also check if the vacuum that reaches the EGR valve is enough (check exact number from service manual, from top of head I would say somewhere between 6-8 inHG.
You can do that by connecting a vacuum gauge to the vacuum regulator (the green-white dish) inside the black box. Unless your #17 hose is connected to the intake manifold, it would suck dirty air all the time the EGR system is not working and eventually clog the vacuum regulator.... I know it because it happened to me.


I could never take apart the EGR valve in half as described; I tried once with a dead one in the jy and it just broke in two.

[kentwat]

I followed the manual troubleshooting and finally found it was the little cvc not working inside the black box. You have to have a vacuum pump and a multimeter for testing though. I got a cheap vacuum pump at harbor freight. Thanks to Dr. Snooz for always replying back about following the troubleshooting page. I haven't had a pgmfi light since. I tried several egr valves from pullapart and always the same. I'd drive for a few, it would get warm and the light would come on. That pdf manual rocks!!!!

[pablo3264]

I will definitely try all the troubleshooting from your guy's post but actually i never noticed till 2 days ago that my #17 and i believe #18 hoses arent hooked up to anything on my motor from the black box, i tried looking at the hose diagram under my hood and i cant find where the 2 are suppose to be hooked up, could that be the source of my problems?

[pickupman6]

Do you have a short ram or cai. I know 17 on an accord goes into the breather assembly, along with a few others 28 sounds right. I deleted my black box, so its been awhile. 17 comes off the egr solenoid. I did away with it and took the little black filter boot off my ac idle boost and put it in place of 17. If 17 has been unplugged I would bet the little vacuum cannister in the black box is stopped up. Hold on ima get my manual out and see what 28 is for

[pickupman6]

I see no 28. I see an 18, which hooks right under where 17 is supposed to go. I also see a 23. Its supposed to hook to a metal line close to the egr valve. It runs across the intake and over to that wad of niples on the opposite end of the intake manifold (the bottom one closest to the firewall), again this is for an 87 accord but we have the same mots so it should be the same.

[pickupman6]

Both 23 and 18 go to the fast idle control solenoid. ( The solenoid with with the orange wire in the black
box.

[pablo3264]

I see no 28. I see an 18, which hooks right under where 17 is supposed to go. I also see a 23. Its supposed to hook to a metal line close to the egr valve. It runs across the intake and over to that wad of niples on the opposite end of the intake manifold (the bottom one closest to the firewall), again this is for an 87 accord but we have the same mots so it should be the same.

Ha sorry I tried to edit my earlier reply, i meant 18 not 28 :O

But yeah in my book i believe 17 and 18 are for the fast idle left it in my car...
Also those 2 were never hooked up since i got the car about 7-8 months ago