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Resolved 2G Changing idle as car warms

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killios11

Probationary Member
15
1
Jun 14, 2021
Edwardsburg, Michigan
My eclipse idles at about 1200rpm when first started before settling to about 900-1000rpm. While driving I noticed it was slowly going up every time I stopped and after about 30 minutes of driving it was up to 2200rpm. When I started it the next day it was back to 1000rpm.

Does anyone have any clue what would cause this?
 
Last edited by a moderator:
Solution
What I did was change my isc (idle speed control) valve. Got one off of a guy on Facebook marketplace. I also grounded out my ecu and adjusted the throttle screw. The guy who owned the car before me had lowered the idle with the screw without grounding the ecu so it would start low and climb back up as the ecu tried to readjust it. Between those 2 things mine is fixed. It’ll move 1-2 hundred here and there but that’s normal compared to the 2k before. Hope this helps!
Hi!

Well there are quite a lot threads about idle surge, however it seems that it might be related with the temperature of the engine.

If so, there is a valve that runs with coolant in the throttle body. It's name is FIAV and you can search here how to cloce FIAV, as the ISC can control the idle of the engine wuite good enough.
 
Hi!

Well there are quite a lot threads about idle surge, however it seems that it might be related with the temperature of the engine.

If so, there is a valve that runs with coolant in the throttle body. It's name is FIAV and you can search here how to cloce FIAV, as the ISC can control the idle of the engine wuite good enough.
Thanks! I’ll do more research on that idle surge. I couldn’t find any threads before since I wasn’t sure what to search for.
 
What I did was change my isc (idle speed control) valve. Got one off of a guy on Facebook marketplace. I also grounded out my ecu and adjusted the throttle screw. The guy who owned the car before me had lowered the idle with the screw without grounding the ecu so it would start low and climb back up as the ecu tried to readjust it. Between those 2 things mine is fixed. It’ll move 1-2 hundred here and there but that’s normal compared to the 2k before. Hope this helps!
 
Solution
It may still not be right. Moving 1-2 hundred here and there isn't correct except for up when starting on a cold morning -- say 50 F or below -- or up 100 when the A/C clutch is engaged.

Try a couple of things: With the car warmed up and no accessories, switch the headlights on and off a few times., high beam You should hear a change in the engine sound but see almost no change in RPM, not even temporarily.

Under same conditions turn the A/C on full power and then off. When the clutch engages you should hear the change in sound and RPM should increase by 100 or so.
 
It may still not be right. Moving 1-2 hundred here and there isn't correct except for up when starting on a cold morning -- say 50 F or below -- or up 100 when the A/C clutch is engaged.

Try a couple of things: With the car warmed up and no accessories, switch the headlights on and off a few times., high beam You should hear a change in the engine sound but see almost no change in RPM, not even temporarily.

Under same conditions turn the A/C on full power and then off. When the clutch engages you should hear the change in sound and RPM should increase by 100 or so.
No mines fixed, that 1-2 hundred occurs after warming up after just starting I just didn’t specify. I’m in Michigan so it’s almost always pretty chilly in the mornings.
 
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