Cold Engine Noise Question..
Thread Starter
Racer
Joined: Jan 2005
Posts: 250
Likes: 0
From: Fort Lauderdale/Miami FL
Cold Engine Noise Question..
I have an 01 M6 Coupe w/ approx 30k on the odo. When I start the car after it has been sitting for a few hours & then drive.. I noticed that initially (first few minutes or so).. the engine sounds like it's almost making a faint diesel-like sound. I always start the car & let it warm up for at least 3-4 minutes. Is this a result of an initial cold oil temperature? Perhaps not enough oil in the engine? Anyone have experience or heard of this similar type of situation before? Aside from that.. the car performs nicely. Just interested if anyonelse had any thoughts or feedback. Thanks in advance.
- Matt
- Matt
Burning Brakes
Joined: Sep 2004
Posts: 1,160
Likes: 0
From: Mesquite Texas
There is a thread in C5 general on this..
http://forums.corvetteforum.com/showthread.php?t=992695
I have a 01 and it does the same thing. I just let it warm up a little, over 100 degrees and I'm off and running. Not worried about it at all.
http://forums.corvetteforum.com/showthread.php?t=992695
I have a 01 and it does the same thing. I just let it warm up a little, over 100 degrees and I'm off and running. Not worried about it at all.
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
I had a simular sound last Oct on a cold morning and we thought it could be one of three things 1) pistion slap, 2) bent push rod, 3) exhuast leak from an exhuast O2 sensor.
LSx engines are notorious for the what is called pistion slap when starting up in cold weather. To my understanding and I may not be correct, that is the way it is. Just let the engine warm up for a two or three minutes and drive. Dont do any WOTS.
The push rods in the LS1 engines are not very strong compared to the rods in the LS6 and LS2 motors. But the likleyhood of a rod being bent is small.
The exhuast leak from the O2 sensor or the little tube that runs behind the back of the engine from one side to the other with the O2 sensors are connected to the headers is the most likely canidate. As your engine warms up that little hole that allows the exhuast gasses to leak out and make the noise, closed up and the sound goes away
I good technition will know the sound differene between the three. Too us normal ppl it all sounds like a dissel or a mean azz cam.
Good Luck
LSx engines are notorious for the what is called pistion slap when starting up in cold weather. To my understanding and I may not be correct, that is the way it is. Just let the engine warm up for a two or three minutes and drive. Dont do any WOTS.
The push rods in the LS1 engines are not very strong compared to the rods in the LS6 and LS2 motors. But the likleyhood of a rod being bent is small.
The exhuast leak from the O2 sensor or the little tube that runs behind the back of the engine from one side to the other with the O2 sensors are connected to the headers is the most likely canidate. As your engine warms up that little hole that allows the exhuast gasses to leak out and make the noise, closed up and the sound goes away
I good technition will know the sound differene between the three. Too us normal ppl it all sounds like a dissel or a mean azz cam.
Good Luck
Burning Brakes
Joined: Jul 2004
Posts: 1,164
Likes: 71
From: MA
I have an 01 with 23k and it also makes a slight pinging sould, which goes away when the engine warms up. I thought that it sounds more like pre-ignition (pinging). I was thinking that it an ignition timing problem, perhaps caused by emissions retarding the spark when cold.
