So my service engine light came on in my 97 Z28 while driving down the road. Stopped at an orielly's and had it checked. It was reading the code for the Mass Air Flow Sensor. The thing is it was running normally and i didnt notice anything wrong...missing or rough running or anything like that. Guy at Orielly's said it could simply be a fluke? He went ahead and shut off the engine light. So, what would make it read that code? what usually happens when you have trouble with an MAF or have one go out? What should i be looking for to really be sure theres something wrong with it? Thanks.

 

If the MAF is actually giving bad data to the PCM the car will go into open loop mode where it meters air off of the MAP sensor to determine the mixture and ignores the MAF and O2 sensors. This will result in a rich condition 99% of the time since the MAP fuel tables are programmed to be rich. You probably won't notice much of a decrease in actual driveability. Sometimes there can be weird issues with the connector and the PCM will throw an SES light. Disconnect and reconnect the MAF, see if the SES light comes back. If it does, it could be time to purchase a new one.

 

Was it a po101, if so that is a performance code, usually do to air filter being dirty or a k&n