My 2006 RR HSE with 133K miles recently began making a high pitched screeching sound upon starting the engine. Happens on cold and warm engine starts. Sound / noise lasts anywhere from 2-5 seconds then disappears. Sounds electronic (as opposed to mechanical) and sounds like it’s coming from inside the cabin (as opposed to the engine bay). Sound doesn’t correspond to acceleration or RPMs. Don’t think it’s radio related either. No warning lights or error messages. Vehicle runs great otherwise. Has anyone experienced this type of sound or have any thoughts as to what’s going on? Any help would be appreciated…

 

I think I've read that PCV Valve sounds like an airplane for a few seconds. May want to look into that. Many cars also make a screeching noise if the belts are slipping, especially when starting them. You could try spraying some WD40 on the belts to see if the sound goes away.

 

I appreciate the tip, thanks! I actually think I ‘may’ have figured out the mystery. My “check tire’ light came on yesterday. I figured I was low on air or had a faulty TPSM. All 4 tires had proper inflation. I figured I’d check the spare. It was at 30 lbs. I aired it up and what-da-ya know...the light has stayed off and the shrill sound has stopped. I’m guessing it was a warning chime that has gone wonky. Sounds horrible but since I’ve aired up the spare, it hasn’t repeated.

 

I would've never guessed it! Glad it was an easy fix.