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So I just ran into an issue with my car stalling at idle randomly and pretty frequently.

I thought the issue was my pedal position sensor as it's been throwing codes and EFP intermittently (happened 6 months ago,and then would comeback).

In any case, I had my pedal sensor replaced today and all was well for like 10 miles and then it started happening again.

It's a very strange kind of stalling, like somebody just shuts the car off. There's no bogging or hesitation or RPM hunting. Whenever I shift into neutral or just let the revs drop with clutch in,it just goes below 500rpm and shuts off....sometimes I don't even realize it until I notice I lost power steering and brakes!! Dangerous as well as annoying.

Any ideas? I don't think its the MAF sensors because I just replaced those less than 100 miles ago...
 

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i'd start with the ICV. when the car is idling or coasting the throttles are closed, all the air entering the engine is coming in via the ICV. take it off and inspect, the butterfly inside should move freely when shaken.
 

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i'd start with the ICV. when the car is idling or coasting the throttles are closed, all the air entering the engine is coming in via the ICV. take it off and inspect, the butterfly inside should move freely when shaken.
Does anyone have the procedure for cleaning the ICV? I did not see it in the DIY guidepost thread.
 

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I am fairly lazy so I would pull the top of the plenum and just blast throttle cleaner into the ICV intake. That is the big hole near the front. Then start the car and spray continually for some time controlling the volume to not stall the car. If you want to see things more closely you have to pull the whole plenum.
 

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Take off the manifold and check all your vacuum lines under there and the plastic L fitting (located between 2 vacuum lines). I would also get a new intake manifold gasket and replace it while you have everything apart. Take off the ICV and twist it side to side, the metal flap inside there should move freely, if it doesn't use some carb cleaner and spray it in there while moving the flap up and down.
 

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Also you said you replaced the MAFS 100 miles ago, make sure the intake pipes aren't kinked on the bottom and creating a vacuum leak. Sometimes when you tighten down the clamp it squishes out the gasket on the bottom creating a leak.
 

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Take off the manifold and check all your vacuum lines under there and the plastic L fitting (located between 2 vacuum lines). I would also get a new intake manifold gasket and replace it while you have everything apart. Take off the ICV and twist it side to side, the metal flap inside there should move freely, if it doesn't use some carb cleaner and spray it in there while moving the flap up and down.
Is the intake manifold gasket the rubber boots at the bottom of the throttle bodies? Speaking of which, how do you clean the throttle bodies since I plan to take off the plenum and do a full scale cleaning/vacuum leak check.
 

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Is the intake manifold gasket the rubber boots at the bottom of the throttle bodies? Speaking of which, how do you clean the throttle bodies since I plan to take off the plenum and do a full scale cleaning/vacuum leak check.
No it's the upper one that goes around the plenum, part number 11 61 1 406 657. Just take a rag and wrap it around a screwdriver and clean it while holding the TB's open.
 
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It could be a problem with your fuel pump. I had a similar problem with one of my other cars and the fuel pump was the culprit.
 
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