ericdwong

I'm having issues with my car Lately I've had a bad stumble, sometimes stalling and the car is throwing the P0102 code. No other PCM codes are showing up. At first, I checked around and found a vacuum leak. The PCV hose sprung a big leak, so I replaced it along with the spark plugs. While I was at it, I cleaned the air filter (with Greenfilter cleaner), throttle body (with TB cleaner) and the MAF sensor with CRC MAF sensor cleaner. I figured the PCV hose was the source of the problem, as it was a big vacuum leak.

Buttoned everything back up, and then the CEL came back on I've checked and double checked that everything is plugged in and there were no additional vacuum leaks. It will stall and stumble so I've been driving the Hyundai lately

I then cleaned the G106 ground near the starter wire, thinking it was corroded but it wasn't that bad and cleaned it anyway. No dice

At this point I'm at a loss. Short of replacing the MAF sensor, itself. But before I spend $100+ on a rebuilt/new one, is there a way a home mechanic can diagnose the MAF sensor with a digital multimeter? I don't have the GM diagnosis tool referenced in the factory service manual.

I should mention the car is basically stock engine wise, with the exception of the Calloway Honker and Z06 exhaust. The honker has been on for over 4 years and 60k+ miles. I read another thread where the MAF wire relocated was the cause but the MAF harness wire has not moved from the factory location. Nothing has changed recently on the car. I've never been inside the engine before. It does, however have 205K miles on it. Not sure if the MAF just died coincidentally at the same time the PCV pipe sprung the leak.

Thoughts?

vette747

I have never tried it on my C5, but it worked on my 89. The car (89) was running really bad and stalling. The problem started after I replaced the radiator. No code. I was looking at the manual to troubleshoot the MAF and it is written to disconnect the MAF. When there is no MAF signal, the computer uses some default values. If the car runs better with MAF disconnected, it is the MAF. I disconnected the MAF and the car was running OK. Replace the MAF and problem solve. I guess that even if I was careful removing the MAF when I replace the radiator, I may have damage it.

Anyway, to make a short story, and if it can help, a 5 minutes test would be do disconnect the MAF and start the car. If car runs better with the MAF disconnected, there are good chances the MAF is bad.

Hoping the test would also work on the C5. But it takes only 5 minutes to try.

Maybe the expert on the forum have better ideas.

ZZ06

It very well could be the MAF sensor. R2 and, reset and drive it. I had the Vararam system on my car for years (just recently changed) but I had no problems when the MAF was relocated due to the Vararam. I don't know the voltage that connector is supposed to be but maybe you can check that? How do the pins look? Loose? Funny I came across this thread because im actually going through the same thing. Almost the exact same symptoms. Finally got a code and mine is the P0101. I just ordered a MAF today. Considering I had this issue before the stroker, I believe its my culprit. I will say the problem has gotten worse since the LS6 was in. Whats strange is WOT tunning on the dyno did fine. It seems to have its issues under low load. It even stalled on me last week right before I passed through the base gate. Talk about embarrassing. Considering my MAF has been through a few K&N cleanings, im sure ive accidentally over oiled it atleast once if not more. Plus a hydro locked motor....I believe my MAF is done. Will report back when it arrives next week.....

ZZ06

My MAF arrived in the mail today....well wasn't the problem. I went down the road and it happened again. Only small stutter but enough to let me know it wasn't the issue because it tripped the code again. I believe my issue was somewhere in the tune. I was already on my way back to my tuner because I removed the cats and wanted to see the difference on the dyno. Plus, make sure nothing needed adjusting during WOT. Well removing the cats did lean it some and he made corrections. Anyway, I spoke with my tuner about the stutter and "falling on its face" and he played around a lot with the throttle on the dyno, varying rpms and made some adjustments in the VE table (not sure what). The car drives MUCH smoother and on the whole ride home never felt a small hesitation in the slightest bit.

73Corvette

Thanks for posting what you found that worked out for you... glad it's running smooth.

ericdwong

Just wanted to post a follow up to this thread in case someone finds it via search. Pretty sure I finally nailed this down- I never replaced anything and monitored the car springing the code on and off sporadically over the past few weeks. Eventually, I wound up jiggling the MAF sensor wire while the car was running and could hear a noticeable change in the idle. I measured 12 volts DC from one of the wires, the other was the ground and the other showed 5 volts, so the wiring/PCM seemed ok.

Everything looked OK too- the weatherpak pins weren't corroded or anything, but after experiencing a loose connection with my air pump weather pack, I figured at this age and mileage anything was possible.

I bent the 3 pins on the MAF to give greater contact to the female terminal and believe this has solved the problem. I did this on Friday and just went on a 500+ mile round trip from my house near Baltimore to the Catskill Mountains in NY. Never threw a code and ran perfect the whole time

73Corvette

I LOVE successful updates! Thank you for taking the time to post your results

MadDogZ06

Yes, THANK YOU for posting the final fix. Very few people take the time to do this. It is what makes this forum so valuable.