1UZ VVTi Strange Idle
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1UZ VVTi Strange Idle
I have a 2000 SC 400 with a rather odd set of symptoms; a search here and elsewhere has not yielded anything quite the same. Here it goes:
With the transmission in "park," the engine idles normally. With the transmission in "neutral," the engine idles normally. With the transmission in "drive," however, the idle drops to about 300rpm, accompanied by quite a bit of shaking and a check engine light. Once I rev it, the check engine light disappears and it runs smoothly. I have no idea why this occurs only with the transmission in "drive."
With the transmission in "park," the engine idles normally. With the transmission in "neutral," the engine idles normally. With the transmission in "drive," however, the idle drops to about 300rpm, accompanied by quite a bit of shaking and a check engine light. Once I rev it, the check engine light disappears and it runs smoothly. I have no idea why this occurs only with the transmission in "drive."
#3
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I almost have the same issue, except it doesn't go down to 300RPM and I don't get a CEL.
I've checked for leaks and also tried cleaning the throttle body. Usually I'd either shift to neutral in traffic or turn the AC on and the RPMs will go up.
I've checked for leaks and also tried cleaning the throttle body. Usually I'd either shift to neutral in traffic or turn the AC on and the RPMs will go up.
#6
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No sure but I too noticed my 99 SC400 idles at 300 rpms sometimes at 250 rpms when at a stop and in D. foot on the brakes. However it is smooth as silk and never miss a beat. I did a full tune up, brand new everything including all vac lines. Still idles low when at a stop but always silky smooth. No CEL or anything, so I don't worry about anymore.
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Hey, sorry for my slow reply. Thanks for the comments, everyone. I bought a code reader and plugged it in; it says "misfire detected" for cylinders 1, 2, 5, 7 and 8. What could cause that? The most I've done under the hood is rebuild the starter motor 11 months ago, and the car has been in storage since then (had a lot of personal crap going on). 91 octane gas, always.
Last edited by supra9398; 03-15-18 at 11:43 AM.
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Something major (fuel system, ECU, etc.) would likely affect all eight cylinders, yet something minor (coil, spark plug) would only affect one. I have misfires in five cylinders, for which I am at a loss for an explanation. Perhaps fresher gasoline could solve the issue, or is that overly optimistic? I am hesitant to try anything, as I do not want to damage it.
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No, I did not add any fuel stabilizer; I always doubted the effectiveness of such things. I will try BiGEZ's suggestion and see how that goes. I will update tomorrow.
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I have put fresh gas in it, and while the check engine light no longer illuminates and the code reader no longer detects a misfire, it still idles just above 0 and feels quite rough.
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