Weird rattle during light acceleration...

[ACoupe]

I've just started noticing a weird rattle from beneath the car during light acceleration, 1, 2 and 3rd gears, that goes away once in 4th and 5th or under hard acceleration.It's coming from mid-car.It's a 2007 Auto Coupe.I've also noticed it being a little louder when the AC is on...

Any ideas? I can't get it in to the dealership as I'm leaving on vacation for a week, but am curious as to what it might be...

[telcoman]

I've just started noticing a weird rattle from beneath the car during light acceleration, 1, 2 and 3rd gears, that goes away once in 4th and 5th or under hard acceleration.It's coming from mid-car.It's a 2007 Auto Coupe.I've also noticed it being a little louder when the AC is on...

Any ideas? I can't get it in to the dealership as I'm leaving on vacation for a week, but am curious as to what it might be...

I have no idea but here is what I would do If I were having this problem just prior to leaving on vacation.

!- Open the hood and inspect everything & check all fluids, belts hoses, etc.2- Check tire pressure when cold3- Have someone rev up the engine while the hood is up4- If nothing shows up get the vehicle up on a lift for an under vehicle inspection.5- If still nothing turns up then a warranty trip to the dealer may be necessary or just ask them to just drive to your house with a loaner.

Good luck

Telcoman
Modified by telcoman at 6:58 PM 8/25/2009

[ACoupe]

Sounds like a plan!Thanks for the suggestion I will do so tonight and see what I can see.

[jardolei]

I have the exact same problem!

Please post if you find the solution to it, as I'm very interested to know what it is.

Its so annoying, especially when theres plenty of ppl around

[Poyzinous]

It just sounds like something is loose. Unless you're hearing engine rattle. Use Premium fuel. But I've seen everything from heatshields loose to debris. For some reason, the underbody of the G coupe takes a good beating to road issues

[curtiscr87]

i have a 04 coupe and mine also does this i just started hearing it. also let me know if you find something

[cheapazz]

check your exhaust real close. Mine does it when the pipe isn't up to temp yet. Real annoying almost purring type of rattle? Especially when in reverse? Alot worse in winter. Just a thought.

[Joey666Crack]

Mine does it too. I'm hoping it's just a small exhaust rattle. It usually only does it at lower rpms. I don't think it's a fuel deal, because i've never put anything less than premium in my tank.

[ACoupe]

Well, got back from vacation and took the car in.The service agent said it might be a heat shield, they checked and everything was fine, nothing loose at all. I had an oil change and since then I haven't noticed the rattle, which is disconcerting...

I only use premium (Sunoco 94), I use synthetic oil as well.

I'm due for my 48 thousand km servicing and he said he can have a technician take a look if it's still rattling by then.I'll let you guys know if he finds anything!

[ACoupe]

Ugh, no rattle now, but there is a series of clicks when I'm in 1st and engage the throttle and even shift to 2nd gear. I guess it IS a transmission issue. I will have to get the car in ASAP...

[Sentientbydesign]

Ugh, no rattle now, but there is a series of clicks when I'm in 1st and engage the throttle and even shift to 2nd gear. I guess it IS a transmission issue. I will have to get the car in ASAP...

I assume this is a 6mt?

Try this. Put it in first, get up to 2500rpms or so (in gear=moving 10mph or so), then tap the throttle hard and release. Do this with your windows down. Preferably near a large wall so you can hear the car better.

If it makes a click...click sound, then it's likely your rear axles that need to be greased, retorqued, and I believe they put locktite on the treads. There's a TSB for it.

[greg_atlanta]

Sounds like the exhaust resonators, I have the same problem on my G. It's considered "normal". Some people like the sound, I think it sounds cheap. I notice it most on high RPM upshifts from 1-2 and 2-3 where the RPMs drop quickly between upshifts.

[watedog18]

I have the EXACT same problem when i back out of the garage and start down my hill about 20 feet down, the brake pumps in real hard and i hear a loud grind, its been like that for months! ive taken it in twice trying to identify the problem but you know how those tings go, heres what I want you to do, im guessing you have the automatic like me, if thats the case, when you first start it up, put it in manual rather than drive, then start off on down the road, dont dog on it in first or anything just give it a sec, and dont shift up, if im right youll still hear the noise, i was freaking out thinking i had a transmission problem untill i did that randomly one day by complete accident and low and behold, it happened anyway, so at least on mine, its not the transmission, its something else, every time it happens it sounds like its coming from directly in front of me in the car, idk maybe its not the same problem but it sure sounds like it

[Sentientbydesign]

I have the EXACT same problem when i back out of the garage and start down my hill about 20 feet down, the brake pumps in real hard and i hear a loud grind, its been like that for months! ive taken it in twice trying to identify the problem but you know how those tings go, heres what I want you to do, im guessing you have the automatic like me, if thats the case, when you first start it up, put it in manual rather than drive, then start off on down the road, dont dog on it in first or anything just give it a sec, and dont shift up, if im right youll still hear the noise, i was freaking out thinking i had a transmission problem untill i did that randomly one day by complete accident and low and behold, it happened anyway, so at least on mine, its not the transmission, its something else, every time it happens it sounds like its coming from directly in front of me in the car, idk maybe its not the same problem but it sure sounds like it

That would be the ABS self check. Totally not what's being described here.

If you turn the car on and start driving, you'll here a little "thump" with a "settling" sound after it. If you happen to be pressing on the brakes while doing so, you'll get the "grind" which is the ABS testing itself. Not a problem, just a little annoying.