High Idle Problem 1999 Ranger XLT 3.0 Flex

[sv_kalise]

Hello All ...this is my 1st Post. I recently purchased a 1999 Ford Ranger 4WD XLT 3.0 Flex truck. There is one persistent problem that is proving very difficult to solve. It will not idle below 1000 rpm. I took the truck to the Ford Dealer in our area and they replaced the IAC ...but then said "...sorry that didn't fix the problem ...you owe us $267." I now know that continuing down this line will wind up costing me a ton of money. Has anyone else had a persistent (always) high idle problem? Should I be looking at a wiring problem or should I try replacing the PCM or ECM? Appreciate any help or suggestions. Thanks ...sv_kalise

 

[Rick]

First thing I would look for are vacuum leaks. Check the hose and the fitting going to the power brake booster. I've seen those disintegrate and leak. If that's good, check the rest of the hoses and caps for cracks or anything that may have come loose. Vacuum leaks are often the cause of high idle complaints.

Welcome to the forum

 

[sv_kalise]

Thanks Rick for the tip on air leaks ...have not done that yet. Will report on what I find.

sv_kalise...