1999 V70 GLT engine bay noise

Post by **scot850** » 26 Aug 2024, 20:06

My friend has the above car. He has been told the power steering pump is failing. It is noisy on the extremes. However, the noise that was attributed to the pump goes away if you switch the AC on. So it this the steering pump or the A/C compressor or clutch failing.

Removing the serp belt won't help identify the issue. Stethescope may, but why does the noise go away with load?

Noise is more of a loud whine than a knocking or graunching.

Neil.

Post by **MoVolvos** » 26 Aug 2024, 21:37

scot850 wrote: ↑26 Aug 2024, 20:06 My friend has the above car. He has been told the power steering pump is failing. It is noisy on the extremes. However, the noise that was attributed to the pump goes away if you switch the AC on. So it this the steering pump or the A/C compressor or clutch failing.

Removing the serp belt won't help identify the issue. Stethescope may, but why does the noise go away with load?

Noise is more of a loud whine than a knocking or graunching.

Neil.

.
Since the noise goes away with load. Try tightening the belt to simulate added load and check noise. A loose belt on a sloppy bearing maybe causing the noise. Remove the belt and check play in any of the mechanical parts.

Another method would be strategical spray water into the suspecting area for noise reduction. Can use lubricant after finding the part to verify.
.

Post by **scot850** » 26 Aug 2024, 23:57

Good idea. Not sure if he still plans to swap the pump anyway. I did suggest if he does to check the other parts for wear and rattling noisy bearings in any of the moving parts.

I will pass this on. Many thanks.

Neil.

Post by **misha** » 27 Aug 2024, 00:54

Probably the serpentine belt tensioner roller...or the belt itself.

Post by **scot850** » 27 Aug 2024, 08:20

Excellent suggestion. I'll let him know to check this. I did offer to help but he doesn't like to ask for help. I'll help when he asks for help.

Thanks again!

Neil.

Post by **abscate** » 28 Aug 2024, 04:15

PVC pipe is great for this. It isn’t a bad idea to do this when things aren’t noisy to get a sense of what normal noise is. Alternators whir, pumps chuff,

Post by **scot850** » 28 Aug 2024, 08:20

I guess we will see. He only told me about the noise disappearing when he turned on the AC as he was leaving, so I did not get a chance to look further. The pump is definitely very noisy on full turn. So a good cheap used power steering pump and an ATF flush will hopefully be the fix for that part. Again, I don't think is is one issue. If we had more time I could have pulled the serp belt, but he had to go.

I have a stethescope too, but again no time to use it.

Neil.