1990- Honda accord- Fast Idle Problem
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1990- Honda accord- Fast Idle Problem
Hello,
I am looking for assistance and troubleshooting a 1990 Honda Accord that has a high idle problem. When I fire up the car it will stay at around 3,000 RPM and not go down.
I replaced the idle solenoid and Idle air control valve. And by replaced I mean I got two at Pick-n-Pull to test and troubleshoot. From what I can tell these are not the source of the problems. I've also ensured that my coolant is up to level.
In addition to troubleshooting with spare parts from Pick-n-Pull, I've also removed these and deep clean them and blew them out with compressed air, flushed them out with carb cleaner and clean them with a wire brush.
Where would you troubleshoot next? What am I missing? What else controls the idle?
Here's a video that helps demonstrate what I'm talking about.
Link to Video
Any help is appreciated!
I am looking for assistance and troubleshooting a 1990 Honda Accord that has a high idle problem. When I fire up the car it will stay at around 3,000 RPM and not go down.
I replaced the idle solenoid and Idle air control valve. And by replaced I mean I got two at Pick-n-Pull to test and troubleshoot. From what I can tell these are not the source of the problems. I've also ensured that my coolant is up to level.
In addition to troubleshooting with spare parts from Pick-n-Pull, I've also removed these and deep clean them and blew them out with compressed air, flushed them out with carb cleaner and clean them with a wire brush.
Where would you troubleshoot next? What am I missing? What else controls the idle?
Here's a video that helps demonstrate what I'm talking about.
Link to Video
Any help is appreciated!
MM Gruppe B
Joined: Feb 2009
Posts: 7,027
Likes: 109
From: 94577/Gaillimh
Re: 1990- Honda accord- Fast Idle Problem
Did you inspect the FITV?
Fast Idle Thermo Valve
https://honda-tech.com/forums/honda-...tv-tb-1844067/
Over time it can loosen up and keep the idle high.
However if it is 3K that may be a vacuum leak, check PCV and brake booster lines as well as all other vacuum lines attached to the 'boost valve' that is attached to the end of the plenum.
Spray TB cleaner around intake maifold and TB gaskets as well as injectors.
If this has just started happening, recheck any recent work done. Even if it was not engine related something that 8s engine related may have been disturbed.
Fast Idle Thermo Valve
https://honda-tech.com/forums/honda-...tv-tb-1844067/
Over time it can loosen up and keep the idle high.
However if it is 3K that may be a vacuum leak, check PCV and brake booster lines as well as all other vacuum lines attached to the 'boost valve' that is attached to the end of the plenum.
Spray TB cleaner around intake maifold and TB gaskets as well as injectors.
If this has just started happening, recheck any recent work done. Even if it was not engine related something that 8s engine related may have been disturbed.
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