What is that noise?!

[Baby 'Maro94]

Hey, I've got a 94 3.4 v6 camaro, and its making a horrible noise!! It happens at two different times. One, when I first start the car it does it, and has happened when it is hot and cold. (Referring to weather and temp of engine). Its a rattling growling kind of noise. Really metallic sounding and very loud. It will start while I'm barely going and on the gas, and stop when I let off, or start while I'm not on the gas and stop when I push on the pedal. It also does it when I'm going about 50 mph. As I accelerate, it "growls" through 49-51 and then just stops. Does it in every gear (P, N, D, R, 1, 2). Anybody know what it could be?

[TraceZ]

Remove the accessory drive belt and test it to see if it is the drivetrain or an accessory.

[LS1 TA]

Maybe a cracked or broken flex plate. Or maybe a torque converter bolt came out. Is the noise coming from under the car, or under the hood?

[TODD 2000 V6 CAMARO]

Hey, I've got a 94 3.4 v6 camaro, and its making a horrible noise!! It happens at two different times. One, when I first start the car it does it, and has happened when it is hot and cold. (Referring to weather and temp of engine). Its a rattling growling kind of noise. Really metallic sounding and very loud. It will start while I'm barely going and on the gas, and stop when I let off, or start while I'm not on the gas and stop when I push on the pedal. It also does it when I'm going about 50 mph. As I accelerate, it "growls" through 49-51 and then just stops. Does it in every gear (P, N, D, R, 1, 2). Anybody know what it could be?

Ya know, man, I have had what sounds like the same problem from my car for the past couple of years. It doesn't seem to be anything that is hurting anything, cause I haven't had any SES lights or any other problems with the car, other than the fact that that noise is incredibly annoying and seriously takes away from the sound of the exhaust. The nearest that I have come to isolating the source of the noise is that I noticed that there are several pebbles trapped between the catalytic converter and the mesh screen looking deal that wraps around the cat. I can't really tell if that is it or not, though. The only other thing I can figure is that maybe the inside f the cat is coming apart and rattling? I dunno. I have stuck my head in the engine bay while it was running and it always sounds like it is coming from underneath the car and not from the engine. I have asked about it on here and no one seemed to know what it could be. Maybe someone else will read it this time and help us out. Let me know if you have any luck, and I will keep you posted if I figure it out. Good luck, man.

[Baby 'Maro94]

under the hood

[Baby 'Maro94]

Ya know, man, I have had what sounds like the same problem from my car for the past couple of years. It doesn't seem to be anything that is hurting anything, cause I haven't had any SES lights or any other problems with the car, other than the fact that that noise is incredibly annoying and seriously takes away from the sound of the exhaust. The nearest that I have come to isolating the source of the noise is that I noticed that there are several pebbles trapped between the catalytic converter and the mesh screen looking deal that wraps around the cat. I can't really tell if that is it or not, though. The only other thing I can figure is that maybe the inside f the cat is coming apart and rattling? I dunno. I have stuck my head in the engine bay while it was running and it always sounds like it is coming from underneath the car and not from the engine. I have asked about it on here and no one seemed to know what it could be. Maybe someone else will read it this time and help us out. Let me know if you have any luck, and I will keep you posted if I figure it out. Good luck, man.

Yeah, my SES is on...but I've taken it to a mechanic (who is not really helpful, but I don't have a choice on who to take it to) and he said the code was reading EGR valve, so they replaced that with no change in the light. Then we reset the computer and all, but the light still comes on only when I'm decelerating. (????) who knows, but they have yet to find out why it's on, except that maybe it's the computer, but is there a chance it is connected to this noise?

[DeWynter]

Sounds like it could be a cracked flexplate, same sysmtoms as my 68 truck had. Metalic grinding snaping noise like a bolt hitting as it spins around on the flexplate. Horible noise at low rpm and when engine was hot or when staring vehicle when cold. Sometimes got better when shifted into gear and/or when stepping on brakes when slowing down to stop.

[white_flight]

Rattlin' cat

I'll vote for the cat guts rattling around. Whack on the cat housing with a soft hammer or wooden stick and listen. I figured mine had the whole cat core busted up, but pulled the tailpipe and the core was intact, but loose. Rattles when you fire it up, rattles when you lug it in first, and rattles at various RPM. It's a '94 LT1, but still passed CA smog last week at 100K miles with the original cat.

[Baby 'Maro94]

How expensive a fix would it be if the problem is any of the above? Thanks for all the help guys!

[DeWynter]

flex plate used from autowrecker was $10 plus time to put it in 1 hour if you know what you are doing, 3 if you dont. contrary to popular thought you do not have to remove the transmision. Steps are:
1) Remove dust cover from trany
2) remove three bolts from torque converter
3) Remove bolts from trany bell housing to engine block after putting a floor jack under trany to hold it up, and a block under rear of motor if you feel you need it, I never do.
4) Remove trany crossmember bolts
5) Push trany back till the driveshaft has slid in as far as it will go, should net you 1.5 too 2 inches of space between engione block and trany.
6) use long breaker bar to remove flexpalte bolts from crank.
7) Pull out flexplate.
8) Do revese with new flexplate. (remember to torque the flexplate bolts)

If you do not know what any of the instructions mean, you may need help or bring it to a pro.

[LS1 TA]

If it's the flex plate and you do it yourself $30. Or if your lucky, maybe a torque converter bolt came out, in which case $2.

[TODD 2000 V6 CAMARO]

flex plate used from autowrecker was $10 plus time to put it in 1 hour if you know what you are doing, 3 if you dont. contrary to popular thought you do not have to remove the transmision. Steps are:
1) Remove dust cover from trany
2) remove three bolts from torque converter
3) Remove bolts from trany bell housing to engine block after putting a floor jack under trany to hold it up, and a block under rear of motor if you feel you need it, I never do.
4) Remove trany crossmember bolts
5) Push trany back till the driveshaft has slid in as far as it will go, should net you 1.5 too 2 inches of space between engione block and trany.
6) use long breaker bar to remove flexpalte bolts from crank.
7) Pull out flexplate.
8) Do revese with new flexplate. (remember to torque the flexplate bolts)

If you do not know what any of the instructions mean, you may need help or bring it to a pro.

I guess mine couldn't be this problem, since I have a 5-speed....could it? I know I don't have a torque converter, but could it be the tranny? I'll have to wait until the blizzard here stops (dang crappy weather ) before I will be able to check it out better. Any ideas?

[DeWynter]

I guess mine couldn't be this problem, since I have a 5-speed....could it? I know I don't have a torque converter, but could it be the tranny? I'll have to wait until the blizzard here stops (dang crappy weather ) before I will be able to check it out better. Any ideas?

opps sory didnt realize it was a 5 speed. It could be the trany the borg warner 5 speed isnt the strongest in the world. Check to make sure there is no play in the driveshaft wher eit enters the tail of the trany, coluld have a wrecked bearing. Other than that I guess it could be an A/C or water pump. I dont know what else it could be but pull the belt off the motor like was stated in an earlier post and see if te sound stops than you can narow it down to the accessories. Could even be the alternator bearings going. Worst case senario it could be the trust bearing gone and the crank rubbing on something. Pull and push the crank pully in and out and see if there is movment.

[azkkn]

its the CAT