I hear this thumping noise when I start the car, not every time. It happens more in the morning..could be a little backfire or something else?

 

I think it's that dead cat that crawled up into your engine..


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ok.. seriously.. I've had this happen before too.. I remeber it being something with the AC being left on. Try leaving your AC system totally off and see if it comes back.

 

I get that too sometimes. There was a post talking about it. I think I remember someone saying that it's normal.

 

This is when it used to happen to me. I park on a sharp incline so that the back is much lower. Then I start the car and tap the gas very slightly and puff sounds like a thump. I think it is the gas getting to the engine with a lot of air all of a sudden. Do you park on a hill or touch the gas when the car is cold starting?

 

Dude! I get that too.....I hate to say I'm glad I'm not the only one. I've got a little over 2k miles after 2 months, but it really almost started from the beginning.

The problem is I'm very busy and the dealer I trust is about an hour away, so I haven't taken it in to get it looked at yet. It just doesn't sound right, does it? The sound is most prevelant in the gearshift / center console in mine - how about you??

I'd be curious if others are hearing it - it's pretty noticeable...

 

i have the same thing on mineits been doing it since i got it in april 01 tl it sounds like it is coming from up front.it seems as if it only does it for the first start of the day. but not all the time. i have tried with the a/c on & off same thing, in the garage or out. i just dont get it

 

Yea.. I get that too.. It only happens in the morning.. ANd it only happened like this month when it is getting colder~!! So I guess it is when your car is starting cold..

 

This noise which occurs intermittently on start up is caused by the design of your vacuum controlled motor mounts.Although I do not know specifically why some cars have the noise and others do not Acura has stated that the noise is normal and does not indicate any problem with the engine mount system.Jens

 

Its normal I have had my car for almost 2yrs now.
That sound happens when the car is first started its like a hard knock or thump. I do not here the sound when the A/C is off when I start the car. It happens only when the Temp is slighty cold & the A/C is in the AUTO MODE. For instance say you are having high 80s or 90s Temps in the daytime. The nightime Temp might not go below 75 you leave the A/C in auto mode. When you start the car up first thing in the mourning you may not here the sound. Now if the daytime Temps are in the in the 70s & you have the system set in the same auto on mode. If the nightime Temp drop to say around 58 at start up you may here the thump/knock sound. I find if the system is off in this condition I have not notice the noise at first start- up. Also on start up at anytime turn the key so that the warning lights come on for a second then turn to start it.

 

It happened to my car too. I had my car for 3 month now, started to notice it this month, ( 3K miles). It seems the morning temp is cooler than before.

I think I will try the turn off AC, I never turn the AC off before, thought just leave it in automatic.

 

Thanks for all your replies.
I don't park on a hill and don't leave my AC on when I turn off my car. The problem does seem to happen more often when it's cold in the morning; so far I like the theory with the vacuum engine mount. I am going to call the dealer and see if I can get some answer. Will keep you updated.

 

One more thing, the noise is at left front of the car.

 

It is most likely what they say it is but all I can say is I don't have that thump when the A/C is turned off. If the overnight temp is high 75 I leave the auto mode on & have not had the noise. When temp is lower say 60s If I had the auto mode on I hear the noise at first start up. I use my A/C alot so this has been my observation of 22months of ownership. I never hear the noise after the car has been driven & the A/C was on & then you come back & start the car.

 

The dealer said the car's computer needs to re-learn the winterized fuel that the gas station is carrying for winter, so I should give a couple of weeks to see if the problem still exists. I will keep you updated.

 

I think Jens is going to know better than anyone. You may not have been around here long enough yet to know but Jens *works* at an Acura dealership (the infamous Park Avenue Acura). I'd go with his information before anyone else's....

 

I agree with Painoman re: Jens expertise, however, I always thought it was a slight backfire perhaps due to the low restriction exhaust. Some of the higher-performance GM's do it too. I have been told by the dealer that it's normal among the TL's and MDX's.