Idle Randomly High, Other times perfect

TomFraser

New Member
I had just about given up on fixing my high idle (1600 in neutral, 1000 in drive)

but driving I noticed that it returned to normal for about 20 miles, then went back to idling high

This started happening a day after my maft pro install

Any ideas what would cause the high idle most of the time, but still idle fine very occasionally?

The could it be the isvc? is something clogged that might need to be fixed?

I don't honestly know where to start looking, simply because the problem is temperamental

If it helps, i'm running on speed density and perfect a/f ratio at idle
 

jdub

Official SM Expert: Motor Oil, Lubricants & Fil
SM Expert
Feb 10, 2006
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Valley of the Sun
I see you have an '88...does the TB have the air bypass screw on top of it? If so, it needs to be full closed.

A clogged ISCV can/will cause idle problems, but usually on the low side of a normal 650 idle. It will not hurt to clean it. Do you have a little air filter on it?

Any codes?