Car bucks and spits rich, stalls only when it warms up

[waGoN]

Our MAFs don't output voltage like some of the others, so you can't use a multimeter. They output a wave or pulse or some other kind of electonic voodoo.

[I8AV8]

Crap. then how do you know what it's doing without the scanner?

[waGoN]

There are two ways:
First, you can lightly tap it with a screwdriver while idling. If it stalls, stumbles, or generally doesn't like it, then you have a bad MAF. If not, then it might be good.
Second, you replace with another one.

Sorry, but unless you have a high dollar scope, and know how to use it, then that is it.

Actually, 2 and a half ways. Some people unplug it and see if it idles better, but I don't think that you can accomplish much doing that. Also, that will only help diagnose it if you are having trouble with it running at idle.

One other thing to check: You said that you replaced the ignition module, but did you check/replace the coil pack? I still think it is the MAF, but if you have a coil pack handy, you could rule that out.

[I8AV8]

Well, i just got ahold of a friend that has a good MAF and i'm going to go and pick it up after work...

[waGoN]

Let us know how it runs. Oh, a word of advice. Make sure you don't put it in backwards. I have heard of people doing this, and it just doesn't run right when you do.

[IATEAV8]

Mine did this at one point and it was a bad O2 sensor.

[I8AV8]

i did the O2 sensor already!! the only other thing that i haven't changed is the cam sensor. if this works than i'll just drive it til the snow comes. Sean has tempted me into getting his MAF-less system as he's going to an XFI system. it's a little complicated (for me anyway) to jump into this late in the year, but it'll be fun for next year - assuming my wife doesn't find out...LOL!!

[IATEAV8]

I hear ya! I did a lot of work to mine this year and I NEED a FAST for all to perform at best but the wife has cut me off the Buick for the time being... but XFI is for sure my next purchase. Hopefully Jack will get a "new" style one here soon for the cheap!!!!!!!!

[waGoN]

Wow, are you guys twins??

If you want to rule out the cam sensor, just unplug it once it is running. It will put the car into batch fire mode. That way, the timing of it won't affect anything. I doubt that is it, but it is easy enough to check. Don't forget, you can't start the car with it disconnected, you have to disconnect it while the engine is running.

[Mike_g]

Sounds like Andys car years back... he had a crank sensor dying sloooowly
we ended up calling AAA on the way home from Etown and dropping it @ Jacks