Shaking When Idling
#31
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dnguyen, I did change the spark plugs for the Iridium (3297) spark plugs and it helped a lot. However, a very slight shaking can still be felt, but seemingly much less than before the spark plug change. Other folks have posted that they think it has to do with the car software and may be considered 'normal' on a 2002-era car. Yours is a 2004 so I'm not sure.
Out of curiousty, how much did you pay for the car?
Out of curiousty, how much did you pay for the car?
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#32
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Interestingly, my experience over the winter has convinced me that ECM has at least something to do with it. I've run all winter with the AC compressor off. While it started it with a mild shake, over a few weeks, it calmed down to being pretty smooth. The other day, I turned the compressor on and guess what? Mild shake. Weird. I suspect the "adaptive" engine management got used to the situation and made the necessary adjustments.
I will give the air cleaner and plugs a look, however.
Fred
I will give the air cleaner and plugs a look, however.
Fred
#33
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I have a 2002 SC430 as well. I had (have) a mild shake also, with a lot of the same symptoms. Mild shake at stop, with no a/c running. Switch a/c on, and most of the shake goes away. I have 126,xxx miles. Changed plugs, air filter, cabin filter and electronic temperature control module. Shake is still somewhat evident with a/c off. From the sounds of it, and according to people on this forum it sounds like it's my motor mounts.
Not sure how long I'm going to keep the car, but may look in to getting it done. What have you guys paid to have this done? I'll go to Toyota or Lexus, depending on the price. Been to both, happy with both.
Not sure how long I'm going to keep the car, but may look in to getting it done. What have you guys paid to have this done? I'll go to Toyota or Lexus, depending on the price. Been to both, happy with both.
#34
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Folks have mentioned to investigate the motor mounts, but like fpatton (abve) I've decided to give up on this and live with the very mild shake that's remaining after I completed all the previously mentioned work.
dnguyen, your car looks great. I'm not familiar with 2004 pricing, but the low mileage would pull a higher cost. The only concern with your car is the white interior, which I think would get dirty quickly with heavy usage. Best of luck.
dnguyen, your car looks great. I'm not familiar with 2004 pricing, but the low mileage would pull a higher cost. The only concern with your car is the white interior, which I think would get dirty quickly with heavy usage. Best of luck.
#35
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If it is your motor mounts, you really should have them replaced.
#36
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Late to this thread.. FYI I experience the same problem and it was the two engine motor mounts. It was last year and there was 56K on the car (2002) at the time. One was described as broken, the other as "worn" two were replaced under my extended warranty and car is so quiet and smooth while idling sometimes I have to look at the tachometer to make sure the motor is still turning revolutions. If the car goes in for service at a dealer just have them inspect the MMs to see it there is an issue.
#38
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Just bought a 2002 SC430 with 120k miles on it. Took it into the dealer today to get the 120k service and they called and said both motor mounts are broke as well as the rear transmission mount. I noticed Sunday at a red light I could feel the engine vibrate in the steering wheel.....thought to myself....may have a broke motor mount. Dealer wants 540 to replace both motor mounts. I assume the transmission mount probably broke over time with two broken motor mounts. Even though it is going to be an expensive bill...my wife loves the car.
#39
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Folks have mentioned to investigate the motor mounts, but like fpatton (abve) I've decided to give up on this and live with the very mild shake that's remaining after I completed all the previously mentioned work.
dnguyen, your car looks great. I'm not familiar with 2004 pricing, but the low mileage would pull a higher cost. The only concern with your car is the white interior, which I think would get dirty quickly with heavy usage. Best of luck.
dnguyen, your car looks great. I'm not familiar with 2004 pricing, but the low mileage would pull a higher cost. The only concern with your car is the white interior, which I think would get dirty quickly with heavy usage. Best of luck.
I did replace NGK Iridium IX Spark Plugs last weekend. Car in park idle at 900 rpm and it's smooth AC off/on, heater off/on still smooth. Accept, when i put in Drive then shaking very mild off/on. Yeah, that beige color is pain in the butt to keep it clean
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#41
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For what it's worth, mine is an 03, and I had the same sort of symptom- in drive with brake, pretty significant shaking, in neutral, essentially none.
My motor mounts were shot on one side, and mostly on the other.
Since replacement, the shaking is 9x% reduced (i.e., barely noticeable).
I held off on a throttle / top engine clean to know which made the difference.
Between doing that (scheduled tomorrow) and possibly cleaning the air sensor / MAF, that may get me the rest of the way to perfect.
Good luck!
My motor mounts were shot on one side, and mostly on the other.
Since replacement, the shaking is 9x% reduced (i.e., barely noticeable).
I held off on a throttle / top engine clean to know which made the difference.
Between doing that (scheduled tomorrow) and possibly cleaning the air sensor / MAF, that may get me the rest of the way to perfect.
Good luck!
#43
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Motor mounts were 318.24 for the two parts, and then umm, 275 in labor, which I think is about 3 hours at their rate.
I can still feel a difference between neutral and drive, not quite as pristine as VTIBob's experience, but hey, that guy's a flipping wizard, so I expect everything works out better for him just in general!
I'm a newbie, hardly know what's going on- but it may be that he also has a clean MAF (the air sensor thingy), whereas I may not, to make that last little bit of difference...
I can still feel a difference between neutral and drive, not quite as pristine as VTIBob's experience, but hey, that guy's a flipping wizard, so I expect everything works out better for him just in general!
I'm a newbie, hardly know what's going on- but it may be that he also has a clean MAF (the air sensor thingy), whereas I may not, to make that last little bit of difference...
#44
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Have this exact same problem. Slight vibe at idle in park, more or less the same in gear. But more than before. Wife owned the car since new, I've been driving since 25k miles
. 78k mi on a 2002.
Going in this week for the 120k service and new plugs. Curious to see if that makes a difference, and what they say about the motor mounts.
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Going in this week for the 120k service and new plugs. Curious to see if that makes a difference, and what they say about the motor mounts.