1987 Z28, 305 Won't start

[Modracer80]

I have a 1987 Z28 camaro w/ the 305, the engine has been running like shit, miss firing for quite a while, it final quit on me and wont start. We put a new coil, and distributor in it, coil did nothing, the distributor brought it back to life but only for like a half hour then quit agian. The cap, rotor, plugs, and wires, are all 2 years old. We went through the service manual, went down the flow charts, checking every possible item, and we're lead to belive the the ECM is bad. When I turn the key on, the S.E.S. light does not light any more, although the previous night it was blinking, and doing all kind of crazy things while we had it running, and brought it for a test drive, thinking it was fixed, actually quit on the road on me. We checked a good majority of the relays, and other sensor connectors for bad connections, such as corrosion and such, and they were all clean. I have not yet had it hooked up to an OBD 1 diagnostic tester yet, but i did try jumping the connections to get the S.E.S. to blink the code out to me,,but the S.E.S. light wont even come on when I turn the key on.

Im still lead to believe the ECM is bad, but not sure. Alls I know at this point is that Im just going around in circles, and that any help would be emenssly appreciated!


Thanks,
Bob Burgess

[Morley]

If the check engine light won't come on and the bulb is good, the ECM is ka-putt. With not being able to get it to flash out the codes is further evidence pointing to the ECM. See if you can get one from E bay. You are looking for a "165" ECM. That is the last 3 numbers in the GM service number for the ECM and how everyone referrs to them. you can use ANY 165 ECM and the later GM replacements for the 165, GM service # 16198259 . They cover years 1986-1989. The only thng different is your MEMCAL (big prom carrier plugged into the ECM)

[spytearbite]

Battery have 12V? Charging system work? You have spark? Fuel pressure? Compression? Gotta be one or the other.

[Modracer80]

Yea thats what Im figuring on as well. I'm having a buddy come over tonight with a reader to plug in to the OBD and see exactly what the problem is.

And yes, battery has 12v, 45-50# fuel pressure, charging system seems to been working fine, spark isn't the greatest around but it does have spark, and compression is good as well. We tested the compression when we turned it over by hand to find TDC to align the new distributor.


Ill post back with reader results, and thanks for the replys.

Bob

[spytearbite]

I don't have a photo of my HEI, but there is that tiny spark unit in the distributor that my spark or may be on it's way out.

Spark color means nothing. As long as it sparks, compression does not blow it out; that color is what sparks in the air be it yellow, blue; is say if you had points and had a constant arc; it was blue at the points gap is one of the variables of a bad condenser.
So, in a way, that little coil wind may act as a condenser in the HEI is I doubt it, but if you spark, you need to verify it does not sign off is hook a timing light to any plug wire. Now crank the engine, watch for the timing light to show no spark and there is your one of 3 variables to fuel-spark-compression.

[Modracer80]

I had the reader plugged into the car last nite, 9-11-08, and even the reader wasn't picking any thing up. So basically now, I simply going to replace the ECM and hopefully that should bring it back to life.

Bob

[Modracer80]

I had the reader plugged into the car last nite, 9-11-08, and even the reader wasn't picking any thing up. So basically now, I'm simply going to replace the ECM and hopefully that should bring it back to life.

Bob

[Modracer80]

I had the reader plugged into the car last nite, 9-11-08, and even the reader wasn't picking any thing up. So basically now, I'm simply going to replace the ECM and hopefully that should bring it back to life.

Bob