Well my 90 5.0 has been stalling when I put it in park. It doesn't stall when I first start it, just after it's been running a while. Could the O2 sensor be causing this? I'll bet mine is pretty old. Thanks
Pull the codes, test the TPS & IAC, search for vacuum leaks, and <font color=red>ONLY if all else fails</font color=red> adjust the throttle stop screw SLIGHTLY in, but make a note of exactly how far you adjust it so you can put it back if you need to.
It only does it going into park after warming up. No problems with stops or going into reverse. If I let it idle for a few seconds and then put it in park, it dips low then recovers and idles appropriately. Also, how do I "Pull the codes?" Thanks
To get the codes, all you need is a paperclip & a Haynes manual ($12 at any parts store) to tell you how to set up for the test. I could type it, but it would take a while & Haynes is probably clearer anyway. Just read thru it a couple of times before starting since they have some of it out of order. Once you get the codes, you can either search for my "EEC Code List" in this or the truck forum (I can't remember where I posted it) or go to havack's site - he has a copy of it there.
When you do the test, be sure to clear the codes when you're finished so you won't get them again later.
Since this phenomenon is related ONLY to the transmission, I'd have it checked by someone familiar with the AOD - when was it last serviced?
Also, read thru the procedure for setting the idle detailed on your vacuum diagram sticker in your engine compartment - it's usually on the core support or the air filter box.