Idle Problem

van1684

New Member
Apr 19, 2005
44
0
0
chicago
On a cold engine the idle is supposed to go to 2000 rpm or so and then slowly go down to 600 or so in a few minutes. My idle is around 600 when cold and when it heats up it sits around 1000 rpm. It kinda seems backwards. Just got a new temp sensor from Toyota and tested the ISC valve and it opens and closes and the resistances are within limits. TPS is tested within limits also. Any suggestions?
 

mkiii222

Member
Mar 31, 2005
697
1
16
Troy, MI
How do your vacuum lines look? Vacuum leaks are a major cause of idle problems.

Have you had your alternator and battery tested or checked your grounds? Under heavy load (such as AC being on) the car will idle higher. (jj correct me if i'm wrong here, but it's been my experience)
 

jdub

Official SM Expert: Motor Oil, Lubricants & Fil
SM Expert
Feb 10, 2006
10,730
1
38
Valley of the Sun
Warm idle on a 7M-GTE is 650 RPM

A/C on (at ops temp), it should increase to 900 RPM in neutral on a manual tranny.

On cold start, I see 1200 RPM...drops quickly to ~1000 RPM. At ops temp, I have 650 RPM per spec.

Look at this thread on MKIII Tech:
http://www.mkiiitech.com/forum/showthread.php?t=850

You need to check for codes...if you have an adjustment screw on your TB, it needs to be completely screwed in closed on this engine. Follow the steps in the above thread.