Hey everyone! My first post on this forum, and it's for a car trouble I can't find.
anyway
I have recently come into ownership of a 1987 firebird trans-am gta. It has the 350 TPI mated to an auto trans. Car seems to have been in the middle of a restoration before I bought it. It had many problems, but the biggest is that the car runs incredibly rich. When I first saw the car running, I thought someone had already gutted/cut out the cat because it smelled so heavily of gas. But nope, went under to look for exhaust leaks and the cat is right there glowing red hot. Anyway, the car is not throwing any codes that I know of, but it has not been driven for any notable amount of time since I put a battery in it. I let it get up to operating temp once. It ran too hot and killed the ignition module. We took it through a car wash down the street and steam poured out from under the hood. Car sounds like its misfiring at idle and there is minor grey smoke coming out of the exhaust. The fuel economy is also tremendously awful.

I have already given each of the injectors a listen to see if they are clicking.
Car has a new cap, rotor, and ignition module.
previous owner cleaned out the fuel tank and replaced fuel pump/sending unit 3 years ago
Already tried unplugging TPS and MAF. Strangely it did not turn on the CE light for either test.
Checked air filter
Tried to replace the fuel filter, but the line fittings on either end weren't having it.

I got this car for tremendously less than it is worth, and I do not have much to invest right now. I am trying to get the car working well enough to pass MO state safety, and I have been able to fix most of the other problems myself. Except the brakes, but that is for another post.

 

Check the resistance on the injectors with a multimeter.

 

all right, I'll go ohm them out once it cools down out here. What readings should I be looking for?

 

Check the fuel psi regulator vac line for raw fuel, if fuel is in the line, the regulator is bad.

All the injs should have the same ohm reading as each other or very darn close.

Check timing for being correct. {a bit advance won't hurt)

Fuel psi as said below

 

5.7 TPI should be around 16.5, and they should all be very close to each other. Anything less than 15.8 is faulty.

Also, you may want to ohm them cold and hot. I had a marginal injector when cold that got much worse once warm.

 

Was the car always a 350 ? Vin # ? Another possibility is look at the code on the computer chip to see what it’s
from. Although no code a bad cts , injectors , fpr all mentions above can cause extreme rich condition.

 

You should also check some of the basics, There is a Schrader valve on the pass side fuel rail. Get a gauge and check the fuel pressure. Should be about 35psi @ idle and 43psi @ WOT. you can pull the vacuum line from the pressure regulator while idling to mimic WOT. Check your timing, base timing is 6-8 degrees with the EST connector disconnected. Check your plug wires and plugs. You may want to pull each plug to see if it isolated to one cylinder or the whole bank. Check the output of your coil. If you can get a hold of a scanner you can read the stored codes on the ECM. I know my light is unplugged from the dash so yours may be the same.

 

The engine is original. I have the factory order form for this car, and the person who ordered this car chose everything. I also have a /mostly complete/ service history, and I have not found any documentation suggesting any heavy engine work.

 

 

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Update:
I went out and tested all 8 injectors with a multimeter, they all measured between 16.2-16.4
I checked the vacuum lines for raw fuel, (after running the engine for a couple seconds) and all the lines were bone dry. Also did the manifold smoke test while I had the lines apart, but no smoke leaving anywhere (except out the air intake). After turning the engine off, for about 1 second afterwards, I can hear the distinct sound of flowing liquid and what sounds like a vacuum leak coming from the rear of the engine. I do not have a fuel pressure gauge to hook up to the fuel rail, but checking the schrader valve with a ballpoint pen revealed there was in fact some fuel pressure holding with the key out.
the engine compartment smells heavily of gas while the car is running, and this does NOT go away nor get worse as the car comes to operating temp.

CE light is hooked up in this car, it self tests just fine with key in ign off. I am looking at getting one of those usb to ALDL cables off ebay to see what the ECM is doing.

 

Another Update:
After rebuilding the headlight motors in this car, my brother convinced me to try pulling codes from the ECM again. I forgot to mention in my original post that when jumping the diagnostic pin to ground on the ALDL connector, and i don't know why I didnt see this as a red flag earlier, The CE light wasn't flashing at all. Just staying on solid like normal with key on engine off. Unplugging the paperclip and replugging it into the pins causes the check engine light to flicker once when the key is next turned. But that's it. No code 12. nothing. I cannot actually get the car to go into diagnostic mode. I tried measuring voltage across the pins and got about 5.5-9 volts. (The reading kept fluctuating)
Looking around online, It seems that when this happens on most OBD1 cars, Its an indication of a bad ECM. Any way I can try to test this? If it turns out to be bad, should I try scouring Junkyards for replacements, or should I go the aftermarket route? I am trying to invest as little money into this car as possible (I do not have a stable income), so the cheaper the solution the better.
Anyway, this might explain why unplugging random things under the hood had virtually no effect on the engine running, and didn't throw a check engine light or code.
Does this sound like a plausible cause of failure?

 

https://www.ebay.com/itm/304036534874

 

this will work for my car? I thought there were subtle differences between the 350 in the corvettes and the iron heads.

 

1227165 86-89 tpi just use your memcal chip

 

Hello Everyone. I was able to resolve this issue by replacing the ECM and exhaust system. I've been using the car as a daily since.