New ECU Project

[bennettracing]

Hey everybody, I'm getting ready to start up an in depth project on my '88 carbed accord. Just wanted to see if any of the board gurus want to give me a hand or would be interested in it. I've come to the conclusion that my car doesn't run because of a faulty ecu, or, more than likely incorrect readings it is getting from missing/bad sensors and resistors. I want to figure out exactly what every wire on the ecu does and where it goes, also how to adapt to different setups or "hard wire" so that it will run correctly. All of my emissions have been removed before I got the car, with a weber installed, so I'm sure most of the wiring got forgot/left out. I have a great deal of electrical experience, so anybody who's willing to lend me a few seconds of their time with advise and/or help would be greatly appreciated. I've got about half of the wiring figured out, only without the car running, it is difficult to correctly diagnose some issues. Let me know if anybody is interested, and if nothing else, I'll keep everybody updated.

Kyle

[BITESIZE]

All i can say is ha ha ha, that ecu is way too complex for any of us on the boards.

[cruznz]

faq....carotman got the pinouts there ...check it out

[BITESIZE]

By the way I was talking about everything inside of the ecu. The diagram is somewhere in the frequently asked questions. Carotman is the guy to ask about this.

[bennettracing]

Well, I searched the entire listing of How-To's, and I'm not able to find anything like I am talking about. I found the link you are referring to, but that is in regards to the main relay, with a bit about the ecu, unfortunately that is for the efi PGM-FI, which I believe is different than the ecu that comes in the carburated vehicles. Anybody got any ideas?

Kyle

[pimp86LX]

the ecu on a carb'd wont do a helluva lot. So the car doesn't run at all? why not just swap out for another ecu? With your webber and no emissions controls....what does the ECU have left to monitor/manage?

On my 1991 Buick I built my own ALDL->rs232 adapter and wrote some basic software to initiate the proper OBD-1 "Mode" and i could retrieve a stream of data. However i didn't have any sort of frame of reference for all the binary data so i never got it very far. I was able to find the RPM values and the VSS values but that was about it.

Whatever your plans are...good luck! keep us up to date.

[bennettracing]

Well, I'm new to the world of honda, but an ecu should, and does appear to, while not it's main function, should be the ignition module as well. This is why you can't run your car without it in there, because it does the job of say, an aftermarket ignition, like MSD. Basically I'm trying to find a way to bypass all the sensors (many of which aren't there anyway :sad2: ) so that the ecu works only as an ignition module, to control spark. I've thought about replacing the ecu, but I'm not sure what another ecu might cost, if anybody has one cheap, it's worth a shot, but this isn't really the board to be discussing that, send me a pm if anybody has one. I'm basically trying to track down where all the sensors and resistors that are inline with the ecu go to so I can modify, and effectively "remove" the object in question. I'm just sitting down with my service manual to get a start, but several of the wires are slightly different, causing some confusion.

Kyle

[k-roy]

The carbureated ECU only controls the emissions system. Since yours is gone it does jack shit right about now. My car does not even have an ECU anymore. Oh and the main relay is only on the PGMFI models.

You either have a ignition, fuel or vacuum issue going on if its not running correctly. If you want you can get an aftermarket ignition box like a MSD 6AL for example.

[bennettracing]

Is there a seperate ignition module in the car or anything? Or are the distributor and the coil the only main parts of the ignition system?

Kyle

[k-roy]

No igniton module, The only wires are the grounds and the 12v from the fusebox, I just double checked.

If you want a cheap ignition upgrade do what I did. Get an Accel coil and a Tec distribuor off of an 84-87 carbureated Prelude. It idles and runs much stronger all the way to redline.

Also you should consider a header and at least a muffler to help flow with the Weber.

[bennettracing]

Update: Allright, thanks for everybody's help, but I ended up reading the service manual like a novel for a few hours, and managed to answer all of my questions. Let me do some thinking, and I'll post what all I found later.

Kyle

[A20A1]

I was gonna say, I've had my ECU and other electrical boxes removed and have no trouble running the car. If anything it runs better with out the ECU and the appropriate modifications to the stock carb.

If it's a starting problem
Make sure you have all the various ground wires hooked up...

If it's a running or idle problem
Check your carb to see if it's leaking vacuum from the base gaskets
or
Check the float valve since it can wiggled loose and is slam on the needle blocking the fuel.

[shepherd79]

if you have problems with ignition, i would directly approch such problems as coil and distributor.
if you still have stock coil, well replace it with aftermarket one. you won't be sorry.
if you still have original dizy, i am sure the bearing or the main shaft on it has one huge play. replace it.

[dXsquared]

damnit... that was a huge waste of my time... i saw his name, and the ECU project thing and i thought it was a company developing an ECU for our cars... then i read CARBED and i was like WTF? carbs dont use the ECU for anything except emmisions...silly newbies

oh well...

Travis

[HostileJava]

Grabbed my attention to, I thought it was going to be somthing like the GM chip that sean is selling.