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Erratic idle

2K views 5 replies 4 participants last post by  Slayerdies 
#1 ·
Ok when I first start my car it idles low.
After bought 2 minutes idling the car idles up amd down and then cuts off.
If I jump right in back out my driveway and then hit brake it cuts off.
Once it warms up it doesnt do this anymore.
Thoughts?
I am thinking idle air control/tps..
 
#2 ·
Try replacing the Liquid Temperature Sensor or the Air Temperature Sensor. The sensor may be bad because it is sensing it is too cold so it gives it more fuel to start the car initially. The low idle sound you hear may mean it is flooded as-well because the car injected all of that fuel. That may also explain why it starts easier when its warmer out. Hope this helps!
 
#4 ·
Check the vacuum lines on the passenger side of throttle body. I had similar symptoms, bought IAC valve and discovered that one of the vacuum lines had rotted away and even ate away part of the metal fitting.

Fixed this by using silicone to "glue" hose back onto the vacuum fitting (let fully harden so that the silicone wouldn't be pulled into engine).

I didn't even have to take the TB off to fix this, but went ahead and removed and cleaned everything up anyway. I did not replace the IAC.
 
#5 ·
Ok I cant find any vaccum leaks.
ECT shouldnt effect this cuz it happens when car is cold and first started.
It has 162thousand miles on it with original IAC so I am leanning towards that.
 
#6 ·
Also wanna add.
Once the car is warmed up it idles steady.
 
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