: One loud knock



oldworld
03-15-09, 05:07 PM
03 escalade 6.0 engine just passed 70K miles

About half of every time I start the vehicle, right at the start, there is one sort of loud "knock". Only one. The engine runs very smooth, never any problems, no knocking at all except on start?

Any one have ANY idea what that might be?
THANKS

themadhatter
03-15-09, 07:04 PM
just a guess but this could be your starter getting ready to fail on you.

shore
03-15-09, 07:30 PM
By knock do you mean metal banging sound or a spark knock ay start-up.

oldworld
03-15-09, 07:31 PM
While it cranks the start makes no noise at all.
I only hear that knock once the engine starts.
Not certain if it sounds like a starter, but I will have it checked.

oldworld
03-15-09, 07:33 PM
Sounds way too loud for a spark plug knock

shore
03-15-09, 07:35 PM
motor or tranny mount?

Try putting your foot on the brake and gas and see if it does it.

oldworld
03-15-09, 07:44 PM
It really only happens when the car hits the exact point of starting. Then very quiet always!!

bstiffmanofsteel
03-16-09, 02:00 AM
I had an Eldorado that did that back in the day, it was the head gasket going out. I'd start it up and get a loud knock. Eventually that knock turned into a bang, almost like a gunshot...

Guyz1996deville
03-17-09, 12:37 PM
I have the same thing. It is almost like a pre-detination and the starter shaft kicks out. It is something I have learned to deal with. Almost like a click sound too, that goes with it a bit. Hmmmmm I don't know what the heck it is.

oldworld
03-17-09, 01:41 PM
Almost sounds like a piston ...its a pretty loud clank.
Wonder???
Of course when I go to have it checked out, the noise never makes itself present. As soon as I get it home, its starts again.

:banghead:

bstiffmanofsteel
03-17-09, 04:24 PM
Goodluck. Hopefully its not what the issue I had. Has your lade ever overheated?

oldworld
03-17-09, 07:32 PM
I am the second owner. To my knowledge it has never overheated. For sure never from me.
Any other ideas of what this might be?
THANKS

jwtjwt
03-17-09, 11:34 PM
That is the sign of a GM product. I have been dRiving GM products for 35 years and this is a familiar sound. I have it in my 03 EXT and have the same sound but no Probs yet. My family had a CAD DAVILLE when I was a kid and this is same Knock sound I have heard in GM products. I just think it is a part of the engine design. You never hear Iit in Fords but they don't drive like an escalade.

oldworld
03-18-09, 02:52 PM
Guess I will live with it. Anyone else hear this? Really wondered what it was..

lamar10067
03-19-09, 11:48 AM
I know Exactly what your talking about.....sometimes as soon as you crank the engine it gives one knock just as the engine starts and thats it right? I used to have a Denali that did it, my 96 impala does it, my friend has a Z71 Tahoe that does it, my escalade also does it as well. I believe after a while the starter gets some play in it (very little) this is just a guess but I am almost 100% sure it is coming from the starter or the gears where the starter and flywheel meet. I wouldnt worry about it though because my old denali did it for 70k+ miles with no problems and none of the other cars are having any problems either.

oldworld
03-19-09, 03:38 PM
wonder if changing the starter would take cae of that issue. Other than the sound, does than mean that the starter is beginning to fail? If so, I would like to have it changed..............while under the warranty.