Idling during traffic jam
During normal operating, idling is at about 700rpm.
When car is stationary for about more than 5 minutes (depending on weather), the idling jumps up to about 850 - 900rpm and stays there as engine getting hot due to being stationary.
When car moves up to speed and is cooled by the moving air, idling drops back to 700rpm, but shoots up to 850rpm when stationary again for a while.
I believe it has something to do with the Air Idle Control Valve. Check on you tube on this, I've seen videos on how to repair this.
if overheating at all under any condition, solve that issue first, then if that doesnt also fix your idle problem(most likely it will) then deal with the idle problem
Hello Don, No, car do not overheat, aircon is cold and operating normally. To add on, when we spray water on the manifold area, the rpm drops back to normal at 700rpm.
Could have a intake manifold leak, try snugging up the intake manifold bolts. Also when running the AC there may be a Fuel Injection Idle Speed Stabilizer that is giving you grief. No sure, something to look at because I do not see a Matrix in my store listings that I use. This keeps the rpm steady when the AC is on.
next time use brake clean instead of water to plug the air leak and find it......good find though! plug that leak and shes fine
However, during normal driving, no extended idling of more than 10 mins, all is fine. I have also changed the idling control valve, but no use. If there is a leak, the idling should remain high all the time? But it only happens when idling for about 10mins and above, depending on outside temperature...
Hello All, a update. Confirm no leak found. Problem found with the MAP sensor. We plugged in the OBD scanner and found that after some idling and engine getting warm, the "TARGET IDLING SPEED" jumps from 750 to 850rpm. When we remove the MAP sensor it drops back to 750rpm. Also, when we put a cold damp cloth on the MAP sensor after plugging in, it remains at 750rpm. After changing a brand new sensor, same problem happens. Weird...
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