Dude, you can read code flashes with a jumper wire between the self test terminal and the grey/red wire in your eec test plug under the hood. Screw that s10, everybody knows the bird is better
OBD1 codes suck though, they can be very vague and attributed to many more causes. OBD2 is nice because you know what to expect on almost every car.
Since you are smelling raw gas, I would hook up a fuel gauge and see how quickly you are losing fuel pressure KOEO. If it degrades quickly, you might have an injector sticking open. This will make it run rough and have foggy exhaust that burns your eyes and has a fuel smell. You wont know what you are up against until you do some testing. You may also just have WAYYY too much fuel pressure. My dads old 87 F-150 with a 5.0 would run really bad at idle, but OK on the highway. Turns out his FPR was making him run at 90PSI instead of 40.
I plan to get the clutch in my S10 this weekend so I can get out of this gas-hog company truck they are letting me drive. Then I will get under the hood of the bird. I'll go rent a fuel pressure gauge ($120) and test it for too much/too little pressure. I am fairly certain it's not an injector sticking, unless all 6 are. All of the plugs were wet when I pulled them. Where is the FPR located on this engine?
The OBD1 computer is basically just a comprehensive test - if the solenoids / sensors have continuity they are OK, it will only display a code if something has a shorted circuit or an open / disconnected sensor for example. There are no diagnostics / monitors that are ran to determine operating conditions the same way an OBD2 would work.
You may need to do like ROb said and go back to the basics, check fuel pressure, make sure you have a vacuum line at the FPR .. if the EGR is stuck open, that could cause the engine to run very rough / die .. it might set a code for excessive flow, but if not the only way to tell is if the EGR tube is very hot - it doesnt get as hot when closed and there are no exhaust gasses actually flowing through it.
Youve checked spark outside of the vehicle with a spark plug tester, or just a plug grounded out ?? Should have a nice blue spark, if its dull orange it could be weak from something in the ignition system but if spark is good, and fuel pressure is normal, it could have something to do with o2 sensors, MAF, etc .. getting an incorrect reading and throwing off the air/fuel. Stuck open injector, you might need to ohm check them all, use a noid light/digital multimeter to verify duty cycle or pull the fuel rail with the injectors attached, and turn the key to run to see if the fuel line pressurizes and any fuel leaks out of the injectors ..
I can't get the engine to run long enough for the EGR tube to even get warm. I might go ahead and swap the EGR if that isn't too much work. I'll have to see what it takes to get to it.
For the spark, I have changed everything to do with it. The coil, wires, ignition control module, cap, rotor, distributor, and plugs without any change in performance. I have not actually 'tested' for spark. How would I go about testing with a spark plug grounded out? I've never done that.
The MAF is relatively new, and clean. I also swapped it for a different one without any difference. The o2's are probably about 5-6 years old so they may need to be replaced. When I removed the cats from the exhaust I got a CEL. When I put the SCT chip in (about a week after) it eliminated the CEL and I have never gotten one with the chip in. I was assuming the chip was over-riding the o2 input to the ECU. Also, with it being a cold start would the o2's have much effect?
The only sensor that I can think of that I haven't changed is the TPS. This engine doesn't have a crank sensor (that I am aware of). The CCRM that is in there now came from my wrecked 94 (due to the previous one not running the e-fan). The CCRM harness does have some cracked wiring, but I have done my best to tape them up (I know
) for now. I did that prior to installing the engine. I do have another pigtail I can swap in if that might be my issue.
FWIW, I have had this car intermittently have a very similar problem with running like this. Every-so-often when I would start it, it would run like crap - sometimes die. I would shut it down, wait a second, and then it would run fine. I never put much thought into it because it would run fine for long periods in between those episodes.
Sorry for the novel guys. I want to cover all bases and be as thorough as I can be. I've given you everything I have done, and can think of up to this point. Thanks for your help. I am willing to follow any suggestions.