3.0 vulcan, strange Idle.

Project79F150 · #1 (**permalink**) 11-01-2006, 05:48 PM

Hello, Maybe you guys could give me some help on a problem that I have been having. It is not it a ranger but I have the 3.0 vulcan in a 1992 taurus. It has 125,000 miles on it. I am having a problem with it idleing high. When the engine is warmed up and I go from Drive to park the rpms will go up to 2000- 2100 rpms. It will slowly come back down to about 1200 rpm. In gear it will idle at 1000. I have done a complete tune up, replaced the TPS, IAC and the air temp sensor. I have replace several vaccume lines, taken the whole upper intake off and cleaned it and replaced all gaskets. I have gone over every vaccume line with carb cleaner and no change in idle. I have even tried to replace the PCM and still no change.
When the car is warmed up and you unplug the IAC it goes down to normal. Something is telling the IAC to open to much. I am open for sugestions, I don't want to have to take it to the shop. Thanks guys.

Project79F150 · #2 (**permalink**) 11-02-2006, 11:56 AM

Anyone have any sugestions? I am at a loss here.

RangerPilot · #3 (**permalink**) 11-02-2006, 09:21 PM

Remove the IAC and clean it out good with throttle body cleaner, see if it makes any difference.

Project79F150 · #4 (**permalink**) 11-06-2006, 08:09 PM

I replaced it, and it does the same as the old one did.