The car is a 1990 Bonneville. The car ran great during a ~100 mile trip to meet someone up with car parts. I arrived and had the car off for about 3 minutes during the transaction. The car then would fire up fine but would instantly stall. I cracked the throttle a bit and the the started and would stay going until I let off the throttle. The car has no codes but after diagnosing my TPI formula dozens of times I tried disconnecting the MAF connection and the car would start and run but poorly due to limp home mode, but was enough to get me home. Anyone know what the problem would be? I am leaning toward the MAF dispite the lack of codes or a massive vacuum leak, enough to screw with the MAF.

check the compression in the 6th cylinder for some reason i changed all my electrical and throttle so i turned my tps up and fixed that compression leak and i am runnin good now

It would be good to get a scan tool on that car, especially if you believe it'* the pricy MAF sensor.

i agree with u that is a pricy MAF

It will be hard to get any useable data from my scantool, it is only 160 baud, plus the fact that the car won't run with the MAF connected. I'm pretty sure it is not the MAF, pretty much everywhere I spray carb cleaner I will get a rev up. I probably will change the intake manifold gasets and see what happens.

the ECM takes over after 450rpm'*

It seems like the problem was either one massive vacuum leak or several small ones because an intake manifold r&r fixed the problem. It still seems odd that it would just suddenly happen. Thanks for throwing ideas out there guys. :)

The same thing happened to my car and it was the MAF sensor. My son went to the boneyard and picked up another one and now it runs great!

My GP has been doing this for a few weeks. Nobody on the GP boards has any idea what it is since I have replaced the only 2 sensors they thought it could be. It will run fine half the time. Half the time I will start it up and it won't start and I will have to drive it around keeping my foot on the gas at all times (like when I stop for stoplights and such). But the other half the time it will start up and idle like normal, and I can drive it around like a regular car. And it is completely random when this happens.

But, the car has some other pretty serious problems that need to be taken care of that may fix this problem. (like only running on 5 cylinders) I just figured I would post this because my car is pretty much doing the exact same thing.

PLANT PROTECTION: You say you think your problem was a vacuum leak??? Thanks...I will check for that.

Shawn

[quote="dbtk2"]Yes, my problem was definately a vacuum leak, I changed the intake manifold gaskets, TB gasket, MAF gasket, and new injector o-rings.