Hey all, I just picked up a '95 Z28 and have a couple questions. First off, for some reason the MAF is unplugged. I just thought HMM, and plugged it in, but then the car wouldn't stay running. It seems to run fine and doesn't smoke or anything. Is it possible there's some kind of chip or simulator that is hooked up to the ECU that eliminates the MAF?

Question 2: My blower motor doesn't blow at any speed. Are there any common causes for this on these cars, or should I just check the standard stuff? The zone switch still makes the hissing sound when I twist it.

Thanks and I'm glad to be on the forums.

 

The MAF is probably bad. The trouble lite should be lit. Pull all the trouble codes & go from there.

 

Thanks for the insight. I will do that. However, being a'94,I don't know how to pull the codes. Any advice? Thanks so much

 

The 94 has to be looked at with a OBDI scanner, Can't flash codes on 94s, and most code readers don't work with it.

 

You're either going to have to buy an OBD1 diagnostics scanner, which most, I believe, cost quite a bit of money. Or, you can get one of these, http://www.aldlcable.com/, and plug it into your laptop. They have a free program for diagnostics, called FreeScan, that you can download to pull codes.

 

Will do. The only thing that I think is weird: I have had a MAF go out on me in other cars. In every case, the car wouldn't run at all...I don't know if these are any different.

 

MAP sensor is your backup, in case the MAF is messed up. It's not quite as accurate as the MAF, but close.

 

Some cars like the 94 Z28 have both a MAP and MAF sensor. Some others only have one or the other.

Cars wit both sensors use the MAF sensor as the primary and the MAP asa back up and at start time. The PCM will use MAF data as long as it sees a connection to the MAF, so if the MAF is bad, the PCM will get bad data and the engine will run badly. In this case, disconnecting the MAF sensor will cause the PCM to default to MAP data. However; disconnecting the MAP sensor will probably result in either hard start or no start.

Cars that only have one or the other sensor will not run if the sensor is broken or disconnected, and will run poorly if the sensor is sending bad data.