87 IROC, stock 305 TPI, 5 speed manual transmission. Runs very rich, will burn your eyes out running in garage. Sputters and pops when backing off. Fuel mileage not too good. Otherwise, starts, idles, and runs great. Throwing a 34 code. Replaced MAF with used one from Hawks. Replaced MAF burn off relay, MAF power relay, IAC valve, TPS, coolant temp sensor, ignition module, rotor, cap, plugs, wires. Timing, TPS, and IAC all set to factory specs. This thing is driving me nuts. Could have two bad MAF sensors. How do you check MAF to see if it is bad? Could this be related to the EGR?Any help or suggestions would be most appreciated. I have also replaced the ECM.

 

Ok a few things first Im a little confused you say you have a code 34 and you replaced the MAF sensor and the relays ect did this correct your problem or do you still have the code 34?

 

Did you clear the codes after you replaced the MAF the first time

Once a code is set it will only go away when you clear it and the problem is corrected. You clear the code(s) by disconnecting the battery for a few minutes.

If you visit ebay and get a used factory service manual, they have trouble shooting charts for each code. These charts show the electrical connections of the circuits involved and list a test procedure to isolate the problem and then fix it. You could have a bad elctrical connection or a ground or open circuit in one wire that will cause a sensor/relay to not function correctly. Have you also verified you electrical wiring while replacing the various parts????

I am currently working on a Code 36 (MFA Burn-Off Relay) in my 88 5.7L MFI engine.

 

Still having same symptoms and same code.