noises under car

[mjcek]

My car makes a loud awful noise when I'm in reverse...It also makes a constant sound when driving forward...

It sounds like its coming from under the front of the car somewhere...

Any idea what it may be???

EDIT: I have a 94 Grand Am sedan..

[rixGAphx]

1. Also, please tell us your engine, tranny, and # miles to further help us channel our diagnoses.

2. I *assume* the noises are somehow speed-related, in that they become quicker or higher-pitched as speed increases. Plese confirm.

3. Are the noises clicks, or scrapes, or whines, or thumps, or something else, even musical?

They might be tranny-related, or the other major contender would be CV joints.
We need the above information to proceed.

Standing by,
-Rick

[mjcek]

it's a 4cyl engine, automatic trans,, 156K miles...

It's a loud rumbling type noise when i back the car up...

When I'm driving its a constant rumble it's pretty loud as well...

Also, I noticed that when i shift gears the engine actually moves...i assume this isnt normal????

[rixGAphx]

With that age/milage, it's a good bet that one (or more) of the three engine mounts is bad.

Though the engine 'normally' moves fore-aft about 1" at the top when throttle is applied, you're probably seeing the extreme motion associated with a bad 'torque strut' (the dog-bone shaped lower mount that limits fore-aft play.

Though you might have an engine or tranny problem, there might be nothing more wrong than failed motor mounts which allow metal-to-metal contact from the engine/tranny to the body.
These bad mounts can transmit all sorts of vibrations and noises that would otherwise be indistinguishable.

Do some searches on replacing motor mounts, get a Haynes or Chilton's manual, get some tools and a floor jack, and you can replace these mounts yourself.
Helpful to have an assistant handy, and another vehicle for a parts-store run if necessary.
Maybe $75 for all three mounts? Depends on which model of 4-cyl you have, and I'm not familiar with any of them.

Making sure the tranny fluid is to the 'full' mark is about all you can do at this time.

Then, examine/replace those mounts, and report back if annoying noises are still present.

Good luck.
-Rick

[dnm45227]

I just posted a message w/a similar question. my 97 GA has the same symptoms. I was wondering if it was a motor mount, the noise is louder in the cabin than in the engine compartment. Although I don't see any noticeable movement when throttling the engine (could be in the early stages of failure). At first it only "rattled" in reverse, but has steadily gotten more pronounced and occures in all gears. I was thinking of taking it to a muffler shop to see if it was the exhaust manifold/system or the mounts. Please let me know if you nail down your source, I'll do the same for you.

Thanks Kindly