69gto96z

I have been having this prblem for around a month or so now. I will be driving down the road and the car will jerk for a couple of seconds and then the SES light pops on, showing a P0100. After the car sits overnight and I go start it again in the morning, the SES light is gone and it runs fine. This has been happening about once or twice a week for the last month. Anyone got any ideas what might be causing it? I tried cleaing the MAF, that did not help at all.

ACE1252

http://www.ace1252.com/P0100_1.jpg
http://www.ace1252.com/P0100_2.jpg
http://www.ace1252.com/P0100_3.jpg
http://www.ace1252.com/P0100_4.jpg

Editops, I missed the first page...will correct in a min.
Edit: Fixed

camzaro28

hey ace, now if someone was to do all those test and come back with no problems. what would you recommend?

reason asking, me and another guy off the boards ( who has autotap and we ran that on the car also) did all that and came back with no problems. but i still get the code and my car runs like ***.
like the thread starter mentioned, while cruising it will just die and start back up. or stumble over and jerk for a sec then the SES light comes on.

i am not sure what to do at this point. i either take it to GM and pay an arm and a leg or just deal with it dying in traffic every so often.

69gto96z

I am starting to think that my MAF pigtail connector may be getting worn out. I have unplugged and plugged it in a lot. I am going to replace that and see what happens from there.

ACE1252

If your absolutely sure there is no circuit problem and have tried another PCM/MAF(known good parts)....it may be professional time. If it's intermittent, they are the toughest problems to find. I'm certainly no professional, just an avid 4th gen enthusiast. That and the fact I prefer to fix it myself(if I can)....saves money usually.

ACE1252

I think that's a good move if the connection is questionable. I remember on a Car and Driver build up of a Mustang....

They soldered a connection instead of crimping it(as Ford recommended)....turns out that was caused a SES light after the build up was complete. They had to have a dealership find the problem. They must have had a cold solder/high resistance joint to cause that problem....

camzaro28

actually ace i didnt all of them, but most of em. after 2 hours trying to figure it out, i had enough.
i thought it was my pigtail harness also. i ran a wire straight off the battery to where the pink wire would go in the harness and the car ran fine. so i cut it and crimped on a wire to bypass the harness and code was gone for a few days and came back. if that is the problem, maybe it needs a better connection then my crimp job.
GL to all who has this problem, and i hope you figure it out.

Danny McAdams

I have had a few cases of this and that code and running problem, led me to replace the EGR, "fixed it", especially if you are not runing a Cat, EGR's crap easily. camaro409

Injuneer

Just curious... how could a faulty EGR valve cause the MAF sensor to go static?

69gto96z

I havent gotten around to messin with it yet. I had my computer tuned about 2 months ago by MadZ28, and the car ran great for the first month or so and then started doing this. I wonder if maybe it could be in the tune?

Injuneer

Again... the code it for the MAF sensor putting out a steady, unchanging reading. There's no way that problem is cause by the "tune". Either the MAF sensor is faulty, or the wiring harness, including the +12V supply on the pink wire, the ground on the black/white wire or the signal carrying yellow wire are not providing the required electrical functions.

It is a very common problem on the 97 models for the pink wire to be broken, perhaps because of the way the wiring harness is routed. The same problem is seen occasionally on 96 models, and seldom on the 94/95's. Or it may be a problem with a bent pin, for those who haven't changed the pigtail. Apparenly in this case its intermittent, so you might have to try jiggling the harness while testing the wires.

Its very easy to check the pink and black/white wires with a voltmeter, and the yellow wire with a frequency meter.

OneFlyn95z28

Actually I have had to replace both of them on our 95 cars and I do see them bad along with many other ends on alot of the cars we work on

camzaro28

i think i have finally figured mine out thanks to injuneer. i know i have said this before, but this time it makes sense. whereas before i was only hoping it was the problem.
pulled the pcm fuse for 30 secs, started the car. no code SES.
went up to the MAF harness and wiggled it and sure enough the car died down. so i let go. went and checked the car and code was there. not sure if it came on when i was wiggling the harness, but usually it comes on while i am driving and the car dies down.
anyway went back to the MAF and wiggled it some more. everytime i did the car would act up, or die.
so i think it is the harness? anyone know the part #? also how should i go about hooking up the new one. i am not sure if it comes with wires or whatever. do i need to get them soldered?

lt11997

It will come with the connector with a liitle bit of wire already in the connector. The best way will to be solder and heat shrink the wires together. I'll see if I can get you the part number at work tomorrow if somebody doesn't already post it.

I bet it's nice to be back in Florida.

camzaro28

hell yeah it is. and the part # will be greatly appreciated