3vze won't idle

[White Stripe]

I have a 92 3vze. It starts and drives great for the most part. When its cold their are no problems. When its warm and your parked and rev it up it sounds great and idles fine. But when I drive it warm and need to slow down and let it coast in neutral or come to a stop, instead of idling the rpms drop to like 200 where it kinda chugs for a sec and then dies. I replaced the TPS, tested the distributor, checked the coolant temp sensor, tested the AFM. They all seem fine. Any ideas would be appreciated!

 

[flash02]

I have a 92 3vze. It starts and drives great for the most part. When its cold their are no problems. When its warm and your parked and rev it up it sounds great and idles fine. But when I drive it warm and need to slow down and let it coast in neutral or come to a stop, instead of idling the rpms drop to like 200 where it kinda chugs for a sec and then dies. I replaced the TPS, tested the distributor, checked the coolant temp sensor, tested the AFM. They all seem fine. Any ideas would be appreciated!

What type of idle air control system does the 3vze have? More times than not when the idle air control system on an EFI engine starts to wear out it functions great at high RPM but not too good when trying to matin a consistent idle, such as when the engine is warm and or when the AC kicks off or when coming to a stop. Some engines have a completely mechanical idle air control with separate Vacuum Switching Valves (VSV) to independently control high idle for AC and power steering while some have and electronic Idle Air Control System that can increase idle when necessary with out the need for several VSVs.

 

[WristPin]

Air in the coolant negatively affects operation of the idle control

 

[reallifedog]

I went three clicks lean on the VAFM and turned up the idle control on the TB about a half turn. She'll kick up to about 1300 to warm up then stays binned at 850, YMMV.