Originally Posted by Rick88IROCZ

Greetings all,

I have been lurking around the forums for over a year and thought I should join and share my experience with the dreaded code 34.

First some background: I have owned my 88 Iroc (5.7 355 w/ 700R4) for almost 9 years now, and I bought the car from a good friend of mine so I knew a little history of the car before it became mine.

The previous owner overheated the car due to some cooling fan problems and cracked the original block, so after a new block and a rebuild the car developed a rather regular problem with code 34 (Mass Air Flow Sensor). After many visits to the dealership and other repair shops and different MAF sensors the previous owner gave up on chasing the problem and removed the SES light bulb so he wouldn't have to look at the light all the time. The car had not developed any problems with driveability, so it was not a major issue at the time. After I purchased the car it was not driven too regularly due to college and life.

In the past year I dove in to the problem using this forum and any reference books as I could get my hands on to try and solve this code 34 problem. At this point the car would randomly stall at stop lights or even just idleing in park. After replacing the relays for the MAF and the Burn-off the problem persisted. So after reading many posts and articles and actually thinking about how the TPI system works and handles air intake and exhaust I replaced the oil-filler breather cap that was put on the engine way back when it was rebuilt with a new sealed oil-filler cap the problems have stopped. No more code 34 and no more stalling, car runs better than it ever has.

So Thanks to everyone on this forum for there knowledge and the will to share it!