HELP! Check Engine Soon light on

[HPG]

Check Engine Soon light came on. A friend pulled the code 34. My service manual says M.A.F. sensor. We reset the code, and it came back on after just a few miles of driving. Before I replace that expensive part, is there something that may have caused the code to set. 1988 Stock Thanks for any help.

 

[Magmotor]

Check the connector at the MAF....ya might get lucky and it's not making a good connection. You can pull the MAF off and look too see if the 3 tiny burn wires are still there. Check to see if the Burn Off Relay & MAF Sensor Relay are working. If you replace the MAF...it also wise to replace both relays.

Hope this helps....

 

[HPG]

Where are the two relays located Hey c5d can you come over one night and help me with the problem.

 

[stu]

The early c4s have MAF (mass air flow) sensors while the later ones have MAP (manifold absolute pressure) sensors.

The relays are located on the firewall right behind the battery. If you get one then look at the car it you'll know exactly where they are. Ones the burnoff relay and the other is the power but I don't know for sure which one is which.

I replaced both when the ECU started throwing a bad burn off relay code. The things are pretty cheep so I would replace them before replacing the sensor.

 

[geekinavette]

84 uses a MAP system also. MAF started in 85?

 

[RedRagTop]

HPG: I recently had the EXACT same problem and on the same car.
1) Remove the battery
2) Replace the two inexpensive $15 US relays mounted on the firewall right behind the battery.
C4vettes.com has a step-by-step...

 

[HPG]

Hey thanks everyone. I ordered both relays today and will pick them up on Tuesday. I think they are both the same part numbers. I just hope this will correct the problem.