This was posted on corvetteforum.com also, but I thought it would be wise to ask the real gurus!! A friend of mine has an 89 Vette with a six speed tranny. He has been having a persistent hesitation/stumbling off idle for some time, which has progressively gotten worse. The following parts have been replaced: EGR valve, IAC, coil, plugs & wires, CTS, a set of known good injectors recently serviced and matched by Cruzin Performance. A known good MAF sensor was installed with no change in the problem. The TB was removed and all passages cleaned & new gaskets installed. The EGR solenoid had a broken vacuum line that was repaired. No other vaccum leaks were noted. Code 36 for the MAF burnoff module has occured. After changing some of these parts the car initially ran better but the problem quickly returned. The manual for the car states that the MAF burnoff relay is located under the ECM, while a local Corvette repair shop told him that the MAF burnoff and power relays are located on the fender well. Another issue causing some confusion is the Haynes manual listing a MAF burnoff module, while other documentation refers to individual relays. Any help regarding this or ideas about something we may have missed trying to diagnose the problem would be greatly appreciated.

 

The maf module was only used on '85 TPI systems. According to one site the relays are here. And they had this to say about them.