High idle
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Joined: Oct 2013
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High idle
Having trouble with my 91 l98 idles high and has a sluggish start all this started all of a sudden has new iac valve tps throttle body even put new ECM and still the same has new injectors new fuel pump and strainer ies the iac housing wear out where it seats thAt is where all the air is being sucked through need help don't know what to do anymore
Melting Slicks
Joined: Jan 2014
Posts: 2,183
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From: Lunenburg MA
I would look for vacuum leaks first. You can plug all the vacuum ports except the fuel pressure regulator as a test. These cars have a lot of places vacuum can escape, especially with old hoses and brittle plastic tubes.
Thread Starter
Advanced
Joined: Oct 2013
Posts: 62
Likes: 0
High idle
The air that is sucking so bad is from the hole in the throttle body on bottom which leads to iac it acts like iac is not closing enough I can put a rat on it and idle drops if I plug it car turns off I sprayed starting fluid all over vacuumed lines and nothing happens
Melting Slicks
Joined: Oct 2000
Posts: 2,158
Likes: 9
From: N.E. WA
Here are some ideas out of a 91 FSM that may need considered at this point. (at least its easy and free)
Measure (If Installing a New IAC Valve)
• Distance between tip of IAC valve pintle and
mounting flange.
- If greater than 28 mm, use finger pressure to
slowly retract the pintle. The force required to
retract the pintle of a new valve will not cause
damage to the valve.
This is probably not an issue since you already have the new one in.
Reset IAC valve pintle position:
a. Depress accelerator pedal slightly.
b. Start and run engine for five seconds.
c. Turn ignition “OFF” for ten seconds.
d. Restart engine, check for proper idle operation.
If you try that and it doesn't work we can look into the wiring next.
Measure (If Installing a New IAC Valve)
• Distance between tip of IAC valve pintle and
mounting flange.
- If greater than 28 mm, use finger pressure to
slowly retract the pintle. The force required to
retract the pintle of a new valve will not cause
damage to the valve.
This is probably not an issue since you already have the new one in.
Reset IAC valve pintle position:
a. Depress accelerator pedal slightly.
b. Start and run engine for five seconds.
c. Turn ignition “OFF” for ten seconds.
d. Restart engine, check for proper idle operation.
If you try that and it doesn't work we can look into the wiring next.
