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What would cause my rpms to drop to almost 500 and stay there with a rough idle

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What would cause my rpms to drop to almost 500 and stay there with a rough idle

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  #1  
Old 10-11-2018, 04:58 PM
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Default What would cause my rpms to drop to almost 500 and stay there with a rough idle


 
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Old 10-11-2018, 08:59 PM
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Dirty Throttle Body and/or dirty MAF sensor.
Clean both before you do anything else.
 
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Old 10-12-2018, 09:35 AM
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After what bunger said,
Intake leak, check to make sure ALL intake parts are secure from air box to throttle body.
The intake manifold (plastic) on top of the motor that has the throttle body bolted to, has bolts securing it to the motor.
On the I5 they sometimes work them self a little loose.
 
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Old 10-12-2018, 09:41 AM
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I agree with Bunger & Taint. After the easy stuff they mentioned, feel free to review this FAQ thread on topic.

Acts like it wants to stall/rough idle -No CEL -What To Do:
 
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Old 10-13-2018, 11:51 AM
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My H3T Alpha only likes Shell gas. In cold weather it idles rough on cold starts unless it has Shell in the tank. Super weird, and Iíve tried everything including Chevron, Costco, Safeway, Conoco, Texaco, etc., and Shell always works best. So now Iíve memorized where all the local Shell stations are, and Shell is in my quick search on Waze.
 
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