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My SC300 isn't holding idle rpm on its own

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Old 12-27-15, 03:55 PM
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bmatic01
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Default My SC300 isn't holding idle rpm on its own

When I start my car it come on like normal. After a few minutes the rpm's start to try and go below 1100. It slowly creeps below and stalls. I have to give it gas to keep the car from dying. From reading many threads on the forum I know this can be a whole list of things. I want to start with the idle air control valve by cleaning it out and see if that'll help but I want to know what I can clean it with. I am trying to diagnose the problem by using the process of elimination. If this doesn't work then I will be checking the ecu to see if I have leaking capacitors. Any thoughts on this would be nice.
Old 12-28-15, 09:01 AM
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eknine9
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Is there any white smoke coming from the exhaust to go along with the poor idle?

You can clean the idle air control valve with carburetor cleaner, or any heavy degreaser.
Old 12-28-15, 09:08 AM
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z2g2gs
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Check to see if you possibly have a air leak between the maf sensor and the throttle body. Experienced the same symptom on a Toyota Cressida I owned for many years.
Old 12-28-15, 03:06 PM
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1A1
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Look for a vacuum leak. One of your vacuum lines may be cut or torn. If so, un metered air will enter the system and cause it to lean out.

Steve
Old 12-29-15, 03:37 PM
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SCFactory
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Could be vacuum leak, IAC, MAF sensor or TPS. process of elimination really, and check your timing
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