Guys, my 86 Z28 with a 305 TPI I just got has 3 different codes it's cylcling through. It's running pretty rough. I'm stumped as to what to look for. Here's the codes it's giving me.

1-54
2-22
3-44

I know what all these codes refer too, but just don't know what to think. If I unplug the ECM to clear the codes, and then hook it back up and start it, wait for the check engine light to come on, it will give me say code 54. Then, I'll unplug it again to clear, start it back up, and get say the code 44. Code 22 will also come up sometimes. Now this car was sitting for about 6 years in a garage, which I believe cause the body is in good shape. No major rust. Even the paint is fair except for the nose wich is faded. With the ECM acting like this, I'm really starting to wonder if the ECM is whacked out?

ALSO! If i try and hook up a tech 1, it never gets the data. I checked the pins at the ALDL and they are all straight, and clean.

I don't want to be throwing all these parts at it cause money is tight right now.

Here's the questions I need help with.
1-What relay on the firewall is the fuel pump relay?
2-Those with more experience, do you think this is a whacked out ECM?
3-What wires, or connections should I be checking for fuel pump voltage?
4-Can this be a bad fuel pump? When I did a FP test, it stayed around 40psi at idle, and would jump to close to 50psi when given throttle.

I know this is alot to ask, but someone please take the time and help me out, I finally got a Tuned Port z28 with T-Tops and am dying to drive it in the nice weather! ANY SUGGESTIONS ARE WELCOME! THANK YOU!

 

Check to see if you have 5 volts across pins E and A on the ALDL port. If you do, then the ecm is sending data, and your problem lies with your scan tool. If you don't have 5 volts, try to see which pin is the problem. E is supposed to be a 5 volt signal, A is ground.

Fix the ALDL problem, then hook up a scan tool or laptop, and put the key in the accessories position (with the car off). Slowly move the gas pedal down. You should have .54 volts with the throttle closed, and 4.xx volts at full throttle. As you step on the gas pedal, it should climb steadily, in a linear fashin. It shouldn't jerk or drop off. It sounds like your TPS is reading low voltage, and if so, needs to be replaced.

Start the car, and keep an eye on the O2 sensor. You are supposed to replace it every 30,000 miles. Since its that old, and the sensors are less than $25, I would just go ahead and replace it anyway. Once the car is warmed up, the voltage should be fluctuating. These have a tendency of reading lean when they go bad. However, its possible that if you have a fuel pump problem (suggested by code 54), then the car is running very lean in actuality, and the o2 is not a fault. In this case, this code would be a result of the code 54 problem.

Code 54 shows up as :
Low voltage at fuel pump OR
Low voltage at Fuel pump relay OR
Output failure at quad driver module
Pick up a wiring diagram and voltmeter, and check voltage at the fuel pump and fuel pump relay. If both check out fine, then suspect the ecm's quad driver (means replace the ecm).

Good luck.

 

Thank you very much sir. I will try the following suggestions, however I did forget to mention I rplaced the TPS with a OEM ac delco and it didn't help matters any. What's the proper way to adjust it? I'll try and do a search to find out adjustment.

 

Ok, great news guys, I got the car running smooth and on all 8 cylinders. I got a wiring diagram and checked several connections, and the fuel pump relay wiring. They both had not so impressive connections. Corrosion city. Cleaned em all up. I also ran top engine cleaner threw it after I siphoned out all the old gas and filled it with fresh fuel. Also, cleaned the fuel injectors. (Working at a dealership has it's advantages. ) Tried to start it, and it wouldnt stay running. Set TPS voltage it was ok right on the money at .54 volts at idle and 4.xx at full throttle. The car smelled rich as can be, so I gave it one last ditch effort, and pulled the spark plugs I could get too, and sure enough, it was flooded. I cleaned the plugs, checked the gap, unhooked the injectors, cranked the engine to spit out all the fuel, and reinstalled the plugs. This time it started up! I then checked the timing, and was ticked off that it was so far out in Egypt it wasn't even funny. I shoulda known better and checked the timing earlier. Set the timing to 6 Degrees BTC, and she started running like a raped ape!! Thanks guys for all your help!
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Glad to hear you got it all sorted out.