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Quote:

Originally Posted by autoque (Post 760610)

I can reproduce the symptom, actually a more violent one, in about 10~15 minutes.

"more violent"? You haven't met the OP and haven't seen his car, but you are sure your symptom is more violent?

Quote:

Originally Posted by autoque (Post 760610)

What I do is first turn the ignition off and pull the key out. Wait for 10~15 minutes, during which time I do not do anything like opening the door or windows, I just stay put.

Shall we assume that when you DO do 'anything like opening the doors or windows' you cannot reproduce this violent event??????

Quote:

Originally Posted by autoque (Post 760610)

While waiting, I can hear what sounds like HVAC deactivating and then about 10 minutes later I can hear another electric noise which I suppose is some module go sleeping mode.

Quote:

Originally Posted by autoque (Post 760610)

About 5 minutes after that when I turn the ignition on without giving the system any time to wake up at all, the rpm needle goes crazy moving up and down around 500rpm and the engine vibrates violently causing the whole chassis to move about!

When you say you turn on the ignition, do you mean just turn the car on or actually start the car? (I assume the latter.)

"crazy"? What is crazy to you? How much fluctuation? Is it the needle moving or is the engines rpms also varying?

How long does this 'crazy and violent' phenomena last? What is "move about!" to you? Vibrate? Shudder? or is the car and it's chassis visibly moving around?

In all my years of forums, you have got to the the most "sensitive" owner I've ever 'met'...
:thumbup:

A

The tech cleaned the air filter unit but had minimal effect on the roughness/vibration.

So the dealer is ordering the MAF sensor and installing it.

Will report soon if it corrects the problem.

Nope. It's not the air flow sensor.

Dealer says it's fixed. The culprit was the transmission mount. Go figure. Those of you with this problem may want the tech to check it out.

I'm getting nervous. My '08 just started a little shake a couple of months back when starting. Not bad, doesn't last more than 2 seconds, but it is different than what I was used to.

Quote:

Originally Posted by autoque (Post 769416)

About 5 minutes after that when I turn the ignition on without giving the system any time to wake up at all, the rpm needle goes crazy moving up and down around 500rpm

Quote:

Originally Posted by ard (Post 760628)

"crazy"? What is crazy to you? How much fluctuation? Is it the needle moving or is the engines rpms also varying?

Quote:

Originally Posted by autoque (Post 769416)

Dealer says it's fixed. The culprit was the transmission mount. Go figure. Those of you with this problem may want the tech to check it out.

Hard to understand how a transmission mount caused your needle to go crazy and the rpms to jump all around....

Unless maybe nothing change with the operation of the engine, and it was just that the same vibrations and engine operations for the last 40k miles were now more noticeable.... THAT symptom is usually 'mounts'

Dealer updated me on the work they did.

RPM needle moving WAS fixed by air flow sensor way back when I took it in. But it was the vibration part that got them stuck. Because even after replacing the sensor, the vibration still remained.

They kept the vehicle even after replacing the sensor so I thought the sensor didn't fix any problem. And the vibration part was fixed by replacing the transmission mounts.