98 V70 AWD LPT - metallic scraping noise

Post by **renns** » 06 Jun 2014, 16:03

I'm on a road trip right now, and noticed a noise coming from the engine compartment. It sounds like metallic scuffing sound, and does NOT vary directly with engine speed. However, increasing engine rpm does make the sound fade away, so I'm thinking it's like the turbocharger compressor wheel dragging on the housing. Is this a likely cause of the noise? If so, any experience on how long a car can be driven in this condition? I'm hoping to return home (~ 400 miles) tomorrow afternoon. With the engine under load at even 30-40 mph, the sound is nearly gone, and not noticable at all at highway speeds.

I'm not concerned with saving the turbo for rebuild, as I have a guy with a couple parts cars that could supply a used turbo when I arrive home. I'm just hoping for no surprises on the return trip. Any thoughts would be appreciated!

Post by **rspi** » 06 Jun 2014, 17:36

How old are the timing belt parts?

If it were anything to do with turbo wear, there would be lots of smoke and poor performance.

Post a video of the noise if you can.

Post by **renns** » 06 Jun 2014, 17:43

Timing belt, water pump, and all pulleys were replaced about 50k ago. The sound does not change directly with RPM either, which I would expect would happen with any direct engine-driven part.

Post by **renns** » 08 Jun 2014, 12:07

A quick update: The return trip was uneventful, and at the stop for gas after 3.5 hrs driving, the noise was gone. The symptoms appeared after the car was driven and parked in an area of tall grass/weeds at an off-road racing event we were attending. I'm suspecting now that some debris from that parking area was caught somewhere temporarily, causing the issues. All dreams of water pump or turbo swap at the side of the interstate were for naught. I wish all problems would heal themselves in this fashion!