I'm getting high idle at 1100 rpms. Changed MAP sensor and TPS and IAC. I adjusted the throttle screw all the way out and it STILL idled high and the screw was'nt even touching the throttle lever. Could'nt it be the EGR valve or maybe even a CLOGGED vacuum line. I ain't getting any codes so thats good at least. I've sprayed carb cleaner to find the leaks but to no avail.

Ken

 

The IAC/ECM sets the idle. It's a "learned" position.

If you've just done all of this, it (the ECM) may not have
learned it's correct position as yet.

How many start/run cycles have you done since changeout?

sixgun (jjr)

 

possible brake booster

 

I've driven the car at least 50 miles or so. Seems liked it would have learned it by now. In so far as the brake booster...replaced it 2 months ago. The old one finally died on me.

Ken

 

Yea, in 50 miles school's out!

I looked in detail at my '90 shop manual, 3.1 engine, driveability.

The best match to your symptoms is as follows:

TPS Failure or Misadjusted.

It says that if the TPS is failing or misadjusted the ECM defaults
to a mid level value and then ignores the signal. All of this happens
after the ECM detects a TPS code. The next result of this mid level
default is a high idle.

If you have a scan tool, is the TPS changing it's voltage?

The range is like .50v - 5.0V, with idle about .50-.98v.

Then the book gets fuzzy. The ECM will auto correct anything
between .49-.99v and assume it's idle. Hmmm.

Have you scanned the output from the TPS?

lemme know,

Sixgun (jjr)