Tapping/Slapping Noise under car
Thread Starter
Instructor
Joined: Nov 2008
Posts: 145
Likes: 8
From: Nashville, TN
Tapping/Slapping Noise under car
2004 C5 z06, 200k miles, daily driver
Full aftermarket exhaust (longtubes, midpipe, bb bullets)
Past 2-3 months, my C5Z has been having intermittent tapping and/or slapping noise under the car. It does not sound like metal to metal contact. It can do it sitting still at idle, or while moving. Clutch in or out, doesn't matter.
It really feels like a belt has broken and just slapping away on something, but both belts are intact and working.
Increasing engine RPM does not effect it, so I don't believe its valvetrain chatter, or engine internals.
I can feel it thru the pedals and floor.
I have placed my hand on just about every suspension part that I can reach and don't feel anything loose.
I fear it may be time for a clutch, or maybe a throwout bearing, but just unsure. Or maybe torque tube issues. It's definitely coming from the front of the car.
Exhaust feels tight and secure (except for the little movement it requires from motor vibration/pulsing).
Tires are in good shape, all brake components are secure.
Replaced sway bar end links a month ago for general maintenance and installed new lowering bolts.
FR wheel bearing has been replaced, FL bearing feels secure (no play from 12-6 oclock positions), but I read in another thread that bearing could still go out without any play? No grinding or clicking noises.
I'm really at a loss on this one. Any suggestions would help.
Torque tube?
clutch?
Engine mounts?
Full aftermarket exhaust (longtubes, midpipe, bb bullets)
Past 2-3 months, my C5Z has been having intermittent tapping and/or slapping noise under the car. It does not sound like metal to metal contact. It can do it sitting still at idle, or while moving. Clutch in or out, doesn't matter.
It really feels like a belt has broken and just slapping away on something, but both belts are intact and working.
Increasing engine RPM does not effect it, so I don't believe its valvetrain chatter, or engine internals.
I can feel it thru the pedals and floor.
I have placed my hand on just about every suspension part that I can reach and don't feel anything loose.
I fear it may be time for a clutch, or maybe a throwout bearing, but just unsure. Or maybe torque tube issues. It's definitely coming from the front of the car.
Exhaust feels tight and secure (except for the little movement it requires from motor vibration/pulsing).
Tires are in good shape, all brake components are secure.
Replaced sway bar end links a month ago for general maintenance and installed new lowering bolts.
FR wheel bearing has been replaced, FL bearing feels secure (no play from 12-6 oclock positions), but I read in another thread that bearing could still go out without any play? No grinding or clicking noises.
I'm really at a loss on this one. Any suggestions would help.
Torque tube?
clutch?
Engine mounts?
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Melting Slicks
Joined: Jul 2006
Posts: 2,332
Likes: 31
From: Silver Spring MD
Look for something wrapped around the wheels or driveshaft
I had a belt disintegrate on my Montana. Most of it sheared off due to a bad tensioner. Replaced the belt and tensioner and thought I was good. Then heard slapping noises. Looked under but not having a lift didn't see anything. Went on for weeks. Finally noise got much worse. Looked again and saw part of the old belt wrapped around the axel and CV joint. Jacked the car up and started pulling and unwrapping the belt. Took about a half hour as the belt was so tightly wrapped around the shaft it looked like a boa constrictor was under my van. If you live in Florida you might get a real boa and not just a belt. If you can put it up on a lift you can inspect it much easier.
Thread Starter
Instructor
Joined: Nov 2008
Posts: 145
Likes: 8
From: Nashville, TN
Just an update on this issue.
My started went out a week after I started this thread. After dropping the passenger side exhaust (i have longtubes), install the new starter, and then bolting everything back up, I noticed the driver side exhaust had backed itself off at the longtube-cat joint. So I put it all back together.
After driving the car for the past few weeks, I realized I don't hear this slapping noise anymore.
However, today, I had a spark plug wire come loose. It started off as a intermittent miss-fire, but then quickly just became a dropped cylinder all together, just driving on 7. I could hear that slapping noise again, only more aggressively. I knew it had to be the exhaust slapping the tunnel as the engine was running rough due to only running on 7 cylinders. After popping the plug back into place, the motor ran smooth, and the slapping noise under the car went away.
So, process of elimination, the original noise was the exhaust hitting the tunnel under the car.
My started went out a week after I started this thread. After dropping the passenger side exhaust (i have longtubes), install the new starter, and then bolting everything back up, I noticed the driver side exhaust had backed itself off at the longtube-cat joint. So I put it all back together.
After driving the car for the past few weeks, I realized I don't hear this slapping noise anymore.
However, today, I had a spark plug wire come loose. It started off as a intermittent miss-fire, but then quickly just became a dropped cylinder all together, just driving on 7. I could hear that slapping noise again, only more aggressively. I knew it had to be the exhaust slapping the tunnel as the engine was running rough due to only running on 7 cylinders. After popping the plug back into place, the motor ran smooth, and the slapping noise under the car went away.
So, process of elimination, the original noise was the exhaust hitting the tunnel under the car.
Safety Car
Joined: Dec 2010
Posts: 3,938
Likes: 498
From: Fords, NJ
Just an update on this issue.
My started went out a week after I started this thread. After dropping the passenger side exhaust (i have longtubes), install the new starter, and then bolting everything back up, I noticed the driver side exhaust had backed itself off at the longtube-cat joint. So I put it all back together.
After driving the car for the past few weeks, I realized I don't hear this slapping noise anymore.
However, today, I had a spark plug wire come loose. It started off as a intermittent miss-fire, but then quickly just became a dropped cylinder all together, just driving on 7. I could hear that slapping noise again, only more aggressively. I knew it had to be the exhaust slapping the tunnel as the engine was running rough due to only running on 7 cylinders. After popping the plug back into place, the motor ran smooth, and the slapping noise under the car went away.
So, process of elimination, the original noise was the exhaust hitting the tunnel under the car.
My started went out a week after I started this thread. After dropping the passenger side exhaust (i have longtubes), install the new starter, and then bolting everything back up, I noticed the driver side exhaust had backed itself off at the longtube-cat joint. So I put it all back together.
After driving the car for the past few weeks, I realized I don't hear this slapping noise anymore.
However, today, I had a spark plug wire come loose. It started off as a intermittent miss-fire, but then quickly just became a dropped cylinder all together, just driving on 7. I could hear that slapping noise again, only more aggressively. I knew it had to be the exhaust slapping the tunnel as the engine was running rough due to only running on 7 cylinders. After popping the plug back into place, the motor ran smooth, and the slapping noise under the car went away.
So, process of elimination, the original noise was the exhaust hitting the tunnel under the car.
