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stevo909
02-16-2011, 02:49 PM
Hey all, question for you.

I was snowboarding yesterday at the local hill and went to take my gear off. Prior to doing it I thought id start the car to let it warm up a little. So i did, went to the trunk, and proceeded to take my boots off. I noticed the noise coming from the exhaust sounded like I had aftermarket exhaust system on. After about 40 seconds, when the engine idled down to normal, the sound totally went away, basically went to complete silence, almost as if a door had closed.

I searched around a found a couple posts similar, but they didnt really answer the question of is it normal? This quote came from a post i found:

"2. For emissions purposes, these cars run a special mode during cold start. This mode is intended to heat up the exhaust catalyst as quickly as possible to bring exhaust emissions into compliance very soon after startup. This mode contributes to some of the noises you hear. I could elaborate but it would be a long story as lots of things are going on during cold start. "


Is it normal for the exhaust to sound louder upon startup? Its sort of a low rumbling noise. Any light shed would be greatly appreciated.

Hope everyones well.

bigblue
02-16-2011, 03:14 PM
Yes its normal... it has an air pump that pushes air into the exhaust.

stevo909
02-16-2011, 03:17 PM
Yes its normal... it has an air pump that pushes air into the exhaust.

Thanks for the reply....very much appreciated!

Coderedpl
02-16-2011, 03:17 PM
Yep. Totally normal. Had the same thing with stock exhaust and on aftermarket you just notice it much more. thats usually the time i wait for the car to run Before i drive. Usually a min or two after that. Sometimes its longer.

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