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Surging idle. Almost dying.

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Just got in the car. Pulled up to stoplight and all of a sudden the idle starts bouncing back and forth between 500 and 1000 rpm. Almost dying and sounds like crap! NOT COOL!! I'll post video later.


Because racecar.
Arizona, USA
You sure that Sound Tube delete is sealed up properly? What you're describing sounds like a leak after the MAF.

Also check the connections on your PCV lines at the intake and to each valve cover, when I cracked a fitting on my JLT oil separator, the car had similar symptoms.
Yeah, my first thought was the sound tube delete. It's the only thing thats changed. That'll be my first check when I get back tonight. Fantasy Football draft right now!
Mine did that once when I started it with the clutch not all the way down. It sounded like it was running on less than all 8 cylinders & wouldn't improve when I gave it more gas. I shut it down & restarted it & all was good ...Thank God........
ArizonaGT nailed it. The entire plug somehow got blown out so the hole was wide open. I should've known the problem myself. Serious brain cramp.

Thanks again Zona!

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