Ok guys... I'm having a really hard time diagnosing the problem on my car. Heres the story.
92 sc300 stock other than straight pipe exhaust and ram air intake.
When the motor is cold I can start it, will idle around 1500 and as it warms up idle drops to roughly 800 in park. I can drive it around and will be fine zero hesitation. After I have been driving for a while at temp I can shut it off. Wait 15-20 min go out start it and it feels like a vac leak and tries to die then the r's will bounce to a 1100 and hold. If I put it in gear the rpms drop and will almost shut off. But the go to 1000 rpms and hold while on break but If I give it gas it the rpms will drop and then it accelerates. While cruising it will not miss a beat until I push the gas a little harder. If I shut it off and leave the car for a couple mins when It will idle at 1100 but never misses a beat.
It has new plugs ( helped a lil), wires (did nothing), iacv, and good air filter and fuel pressure. Any ideas.

 

When it shuts off/stalls on it's own, a cel light probably pops up. Try and run a OBD1 scan on your
diagnostic port and see if anything comes up. There is a DIY to retrieve codes, just search a little bit.
I had the same problem last year and I cleaned the throttle body, replaced the IACV, and replaced
the MAF. It works fine now (well not "fine" but it doesn't stall).

 

It I've replaced the iacv. Anyone know what other mafs are plug and play

 

Have you ever changed your fuel filter?

 

Yeah I did have a similar problem on my dd and it was an old fuel filter supposed to be changed every 10k

 

i have one for it, and was going to change it but i couldnt get the tanks side on the filter to break free... good o michigan weather.... so I will take it to a shop and have them do it for me. hope that works, because i have dumped enough money into the car so far and still have to fix this mysterious oil leak that only happenes when i turn hard to the left. and gets onto the exhaust and burns which causes smoke to come out from the hood.