2015 v60 R D3 Intermittent screech on acceleration

[dafdaffer]

Hi all. Has anyone had this issue?
Sometimes either in second or third I get a screeching sound during acceleration.
Its when accelerating what I would say over the normal but not full pedal. Like going up a small incline. It appears to be the driver's side. I went the full hog a couple of weeks ago and had the cambelt and tensioner and aux belts changed including water pump just incase, it's done 77000 miles and always serviced. The noise is still there. I tried to record the sound but it wouldn't do it when I wanted it to. When it did it today the engine felt slightly bogged down while it made the noise and picked up when it stopped. But it was minimal. I wondered if it was a turbo leak or turbo bearings but it still goes well and I can't hear noise at any other engine speed or gear.
The noise reminds me of a Hornby model railway ringfield motor when the bushing is dry. Any ideas?

[dafdaffer]

Noticed today that it does not happen when the a/c is on. So maybe the pump bearings

[Tannaton]

On some 5 cylinder engines the belt that drives the a/c pump is a stretch belt rather than having a tensioner and they often do this if you remove them and re-use them (I.e. they permanently stretch and become too slack). I’m guessing the didn’t fit a new one when they did the other belts?

[Kev0607]

Auxiliary belt would be my thoughts, or possibly the auxiliary belt tensioner.

In saying that, it could also be the alternator pulley.

Its a pity you can’t hear the noise when the car is stationary. That would make diagnosis easier.

[dafdaffer]

Originally Posted by Tannaton

On some 5 cylinder engines the belt that drives the a/c pump is a stretch belt rather than having a tensioner and they often do this if you remove them and re-use them (I.e. they permanently stretch and become too slack). I’m guessing the didn’t fit a new one when they did the other belts?

thanks for taking the time to reply

i believe they were changed and look new, the tension for the aux belt was not although he said it felt ok when he spun it up, i have noticed that the a/c pump makes a noise when its been on along time like worn rumbling bearings but the noise that happens is different

[dafdaffer]

Originally Posted by Kev0607

Auxiliary belt would be my thoughts, or possibly the auxiliary belt tensioner.

In saying that, it could also be the alternator pulley.

Its a pity you can’t hear the noise when the car is stationary. That would make diagnosis easier.

100% agree it would be great if it did, i have also had a suspicion over the alternator in the past as my v50's died early, also when i plug my car adaptor into the 12v port or connect the caravan it runs at about 15 volts, its done that for a while mind.

[Tannaton]

The alternator in your V50 that died (and mine....) was a crappy FoMoCo part - not so in the V60.

If it was the alternator then having the a/c off and on would likely make no difference, all my money is on the a/c pump belt either being re-used or a pattern part being fitted.

The a/c systems fitted to the p3 platform often rumble or whine - it’s usually the expansion valve.

[Kev0607]

Originally Posted by Tannaton

The alternator in your V50 that died (and mine....) was a crappy FoMoCo part - not so in the V60.

If it was the alternator then having the a/c off and on would likely make no difference, all my money is on the a/c pump belt either being re-used or a pattern part being fitted.

The a/c systems fitted to the p3 platform often rumble or whine - it’s usually the expansion valve.

I thought the V60 up to 2018 was based on the P3 platform (SPA after 2018). If that’s the case, wouldn’t the alternator be a FoMoCo part, like other P3 cars?

Rumble or whining a/c can also be the a/c compressor itself or the system being low on refrigerant.

To the original poster, I think your noise is belt related. Maybe a squeaking separate a/c belt that rotates the a/c compressor (if your car has one)? I agree with Tannaton on that.

As the main aux belt is new, that rules that out in a sense.

The belt that rotates the a/c compressor doesn’t have a tensioner. Its just a belt that fits very snugly. The main auxiliary belt has a tensioner though. ***Not all models have separate a/c belts.***

[Tannaton]

Originally Posted by Kev0607

I thought the V60 up to 2018 was based on the P3 platform (SPA after 2018). If that’s the case, wouldn’t the alternator be a FoMoCo part, like other P3 cars?

Rumble or whining a/c can also be the a/c compressor itself or the system being low on refrigerant.

To the original poster, I think your noise is belt related. Maybe a squeaking separate a/c belt that rotates the a/c compressor (if your car has one)? I agree with Tannaton on that.

As the main aux belt is new, that rules that out in a sense.

The belt that rotates the a/c compressor doesn’t have a tensioner. Its just a belt that fits very snugly. The main auxiliary belt has a tensioner though. ***Not all models have separate a/c belts.***

Yep the Mk1 V60 is P3 in my understanding but on the Volvo engines I've not seen a unit with a Ford part number on (like on the 2.0D S40/V50 with Denso units) and you don't seem to hear of any going - unlike the S40/V50 where it feels an inevitability before 150k miles.

I'm sure the OP's issue is the stretch belt that drives the AC compressor from the power steering pump or idler puller on some 5-cylinder installations. If you remove the belt and refit it, it stretches a bit more and is more prone to slipping. I'm actually replacing such a belt for the same reason on V70 on Friday...

However I'm not sure if it's necessary to remove the a/c belt to do the cambelt/aux belts. There is a factory tool to fit them without over stretching them.

[Kev0607]

Originally Posted by Tannaton

Yep the Mk1 V60 is P3 in my understanding but on the Volvo engines I've not seen a unit with a Ford part number on (like on the 2.0D S40/V50 with Denso units) and you don't seem to hear of any going - unlike the S40/V50 where it feels an inevitability before 150k miles.

I'm sure the OP's issue is the stretch belt that drives the AC compressor from the power steering pump or idler puller on some 5-cylinder installations. If you remove the belt and refit it, it stretches a bit more and is more prone to slipping. I'm actually replacing such a belt for the same reason on V70 on Friday...

However I'm not sure if it's necessary to remove the a/c belt to do the cambelt/aux belts. There is a factory tool to fit them without over stretching them.

Its not necessary to remove the a/c belt to replace the cam belt. The a/c belt is often neglected for this very reason.

I agree with you, I think the a/c belt is the noise the OP is hearing.

However, if the V60’s were P3’s up until 2018, then that means its a Volvo engine with some Ford parts too, like other P3’s. Unless I’m mistaken…