Wheel bearing type noise...Kind of whirring noise, not real loud but noticeable...But only under acceleration...When I let my foot off the gas the noise disappears...Thanks!

 

Hi viper1996,

What year and model?

Don

 

04 XJR...

 

Do you hear the noise only when moving, or does it occur if you rev the engine with the transmission in Park?

If you can hear it in Park, you may be able to track it down with an inexpensive mechanic's stethoscope or a long screwdriver or socket extension used like a stethoscope.

Could it be supercharger bearings? A belt idler pulley?

Cheers,

Don

 

Thanks, It is definitely in the drivetrain...

 

Have you checked the wheel bearings?

If the bearings seem okay, could a failed engine mount be allowing excessive engine movement such that a rotating belt-driven pulley is coming into contact with something it shouldn't?

Have you scanned the system for stored diagnostic trouble codes that might indicate an air leak as the source of your noise?

You're not giving us much to go on.

Cheers,

Don

 

Well, it is a common thing. Firstly, look behind the guard, towards the front of the motor where the ventilation system jolts onto the motor. You'll take note of that they have tin covers on them, one on every complex. One of both are likely kinda free and reverberate with motor pace. Purchase some substantial band clamps and wrap them deliberately around the culpable heat shield.

 

I will elaborate more...Noise is only under acceleration which clears out tires, bearings, etc...Not an engine/tranny related noise...My thoughts are is there anything in the drive shaft area that may cause it...When you let off the gas it totally goes away!

 

Supercharger?

 

The rear engine mount/transmission mount is there. Also the heat shields riveted to the body near the exhaust downpipes can pull loose and come into contact with the exhaust when the engine leans under acceleration.

 

Perhaps check the engine mounts by watching how far the engine rises if you rev it in drive with a foot firmly on the brakes. Try reverse too. Both of mine were separated and although the right side did not show it by engine movement, the left side let it rise up to the limit of the little safety strap.

 

Its hard to explain but I can tell its a rotational noise like a what you hear when a wheel bearing is bad...Thanks for responses!