Sounds like a Diesel at cold start up

[Csabi]

2002 Envoy XL 4.2 starts up and sounds like a diesel engine for few minutes, when warms up the noise disappear and the engine idles nice and quiet.
When driving and accelerate there is this grinding noise coming from the engine.
Anybody have any idea what is wrong?

 

[Molson02536]

2002 Envoy XL 4.2 starts up and sounds like a diesel engine for few minutes, when warms up the noise disappear and the engine idles nice and quiet.
When driving and accelerate there is this grinding noise coming from the engine.
Anybody have any idea what is wrong?

There is a good chance that your Variable Valve Timing Solenoid(CPAS) screen may need to be cleaned. Personally I would just replace the CPAS, but shop around for the best price. They range from $65.00 to $185.00. Depending on where you buy it from.

Also common for the throttle body to build up in carbon, so giving it a good cleaning wouldn't hurt also.

Keep us posted and stay safe.

Molson02536

 

[Csabi]

Thx

Thanks, for the tip,I will try that.