Subtle growling noise coming from front of my Blazer while its in park idling. It's RPM dependent, NOT speed dependent. It does in no matter what gear I'm in. It's the loudest under the front of the blazer. I've stethoscoped everything with a pulley on it, nothing. It almost sounds like the old air ejector pumps if you've heard them.

Any suggestions? Anything is appreciated.

 

What's the oil pressure while in idle?

 

new engine, 60-70 psig.

 

Ok, stethoscoped the oil sump and heard the noise pretty clear. This is a new engine and a new oil pump, what the crap could it be? Oil pressure is plenty high and steady. Could it be the starter or something closely attached?

Any ideas?

 

Who built the motor? Is it possible that a mistake was made and the crankshaft is making noise? Was it balanced?

 

Its a new Jasper crate. They put the insides together, but I guess I need to take it back to the shop that put it in

 

Could be an intermittent exhaust leak at the manifold?