2004 V70 fuel help?!

SteveOV70 · Post by **SteveOV70** » 05 Apr 2025, 06:39

Hi all!! New here, Iv deep dived many hours here and found some great help and still many Q’s!! So here’s my issue. I have 2004 V70 and the garage who used to service it gave me a code of P0259 “A”. I used my personal scanner and it told me “fuel pressure sensor” I replaced that and it went from running to lean to to rich. Still the same problem I was having. I would turn it on and at idle it runs no problem but everytime I accelerate it bogs down and then will stall. I can turn it back on and itl run. I called the garage who used to service it and who gave the code and he told me it was the pressure regulator. Now after searching hours here Iv found that my car either doesn’t have one or maybe it does lol. Looked everyone online and found that the regulator was discontinued and other places say they have them online. Iv talked with parts store and they tell me I have a FPR and others say I don’t. I’d really love to know if this is the issue w my car. If anyone has input in extremly greatful!

Post by **vtl** » 05 Apr 2025, 07:59

What engine?

SteveOV70 · Post by **SteveOV70** » 05 Apr 2025, 09:34

Here’s the info.. 2004 Volvo V70 2.4 L 2435 Cc L5 DOHC 20 valve vin is YV1SW64A942435987

Post by **vtl** » 05 Apr 2025, 09:46

https://www.fcpeuro.com/products/volvo- ... osch-15817

SteveOV70 · Post by **SteveOV70** » 05 Apr 2025, 10:14

Really that easy?!?! Do you know what that code was all about? The p0259a?

SteveOV70 · Post by **SteveOV70** » 05 Apr 2025, 10:17

Oh also I wanted to ask, with a failed OS would you smell gas in the cabin?

Post by **vtl** » 05 Apr 2025, 10:42

Going from lean to rich and backwards out of proportion is usually an old upstream oxygen sensor. MPG and HP suffer a lot in this case. Yours is guaranteed to be old and tired. I sold my 2002 V70 in 2016, and oxygen sensor failed there already.

Don't know whether B5244S6 engine has a fuel pressure sensor (my B5244S didn't have one), what part number did you replace? And if your model year has PEM (basically a signal amplifier for fuel pump). Usually located in the vicinity of fuel filter. Volvo has TSB for relocating PEM to spare wheel well. The last thing is your fuel pump is dying. That would explain loss of power and stalling under load.

PEM-equipped car would let you read the fuel pressure in VIDA. For old school no PEM config you need to measure fuel pressure at the rail.

Post by **vtl** » 05 Apr 2025, 10:45

Is it any different in the morning, when the car is cold? Start it and drive.

SteveOV70 · Post by **SteveOV70** » 05 Apr 2025, 12:07

When the car was originally stalling out the car was warmed up. I was driving on the highway when all that started to happen. It wouldn’t go above like 10mph. Then eventually it would stall out n I’d just restart the car n it would catch not a problem. It was warm. The next day when I went down to move it it was cold. I had swapped back the original FPS and drove it down the st. To my sisters house. It didn’t stall or bog out once!. So what happened was when all that happened I went to the parts store and bought a fuel pressure sensor cause that’s what my scanner said it was. When I put the scanner in my car b4 I I changed out the FPS it was reading lean, but when I put the new FPS on it was reading rich and instantly was stalling out. That’s why I changed out and put back in the original FPS so I could drive it down the street. Since all this has happened I can smell gas more in the cabin.

SteveOV70 · Post by **SteveOV70** » 05 Apr 2025, 12:12

My 04 V70 does have a FPS on the right side of the rail, nothing on the left side, only the tire valve to release pressure I can try n put up a couple pics ina. Couple days of anyone needs to see the engine if that helps? It’s at my sisters house RN lol