2019 VOLVO XC90 don’t ignore this!! Loud noise and a p0171

[@rfassis]

Have the same issue but without the sound. 2016 XC90 T6, P0171 code, engine light on (sometimes I've seen a fuel trim code as well, but it's not there anymore). The car doesn't stall or anything, if it wasn't for bad fuel consumption and the engine light I would never know. Took it 3 times to the Volvo dealership, but they can't find the issue. They re-did the supercharger seal after a smoke test revealed a small leak, they changed spark plugs, and now the rear O2 sensor. Short-term runs close to 0% at idle, and long-term is around 12%. I took the oil cap off and could see there was some vacuum (not much), but it did not impact the engine's RPM at all when I did that. There is also some white smoke coming from the exhaust and the exhaust is also pitch black, but the oil level is stable for many miles, and doesn't seem to be burning oil.
Bought a smoke machine and I'll try to find a vacuum leak myself. I'll also check for the same thing you did, just want to get rid of this damn running lean code!

[@Drescars]

Sometimes on those Volvos you have to reset the fuel trim with a good scanner… or otherwise is like you never fixed…
Look at short term fuel trim at idle and also when cruising. If they are higher at idle, you most likely have a vacuum leak or breather issue, if they are higher at cruising speeds then look for a fuel delivery or air flow meter problem.
I hope this helps and keep me on the loop!!! Good luck

[@zawaprz]

You can go cheaper than that.. just change: PCV Diaphragm, not entire thing.. 10 dollars something or so...

[@Drescars]

Thanks for the input… I’ll look into it!!! But I rather do the entire thing, that way I can give costumer a warranty on the job!!

[@armenvardanyan749]

Hello dear...my car is a 2016 xc90, 320 hp, the problem is p0171, the engine runs with a little noise after dropping the initial rev.

[@Drescars]

I had another one a couple weeks ago same engine as yours with a p0171 a little whistle at idle I smoke test the engine it was leaking at the oil cap the oil ring was mangled good luck mate!!! But definitely smoke test you can buy a cheap on online they work ok!!!

[@jayslabotsky462]

Have you run across one of these with a turbo whistle accompanied by a P0171? The sound and the code might not be related but it seems plausible. 2017 T6 Momentum with 65K miles. The sound is definitely coming from the turbo and not the PCV. (Although I changed the breather anyway.)

[@Drescars]

After replacing oil trap, be sure to reset control unit adaptives, otherwise it will set a lean code… but in the other hand I had a 18 with 45000 that the turbo gasket before cat was leaking causing a lean condition, but I don’t remember whistle… make sure your oil cap o’ring is sealing I heard them making a whistle sound!!! Good luck!!!

[@faisalomar7816]

Any possible way to contact you? I own 2019 xc90 I wanted to discuss- noise coming from the engine. Mechanic replaced the PCV Oil trap similar in your video with a new one, but noise still there. Thanks you!

[@Drescars]

Any codes?? Can you describe it a little??

[@GastroLineGermany]

Which engine is this? D5?

[@Drescars]

I am not a Volvo guy but I think D5 stands for DIESEL 5 cylinders… it is turbocharged also…
This one is a gasoline 2.0 turbocharged called B4204T23