2004 Volvo S60 stalling on the highway

[Brenan09]

Hello everyone, I am new to this site. Trying to find answers for my husbands Volvo.. This may be kind of long but please bear with me;) he bought this 2004 Volvo s60 from a dealer about a year ago, we are the second owners. Test drive went fine, drove it from dc down to va beach. On that drive I made the mistake of filling it up with regular gas (not sure if this is important info, just thought I would mention it) that's when we suspect the trouble may have started? Check engine light came on and it was running a little 'off'..  he took it to auto zone and they had him add some sort of fluid in the gas tank (if it's important to know what I can ask him) the next day it stalled for the first time while he was pulling out into traffic.. Complete loss of power. Re-started right away but still didn't run right. Lots of hesitation when accelerating. Had the codes read and they indicated bad fuel pressure sensor (forget the code number)  Volvo ran the vin# and said it had already been replaced by the previous owner due to recall. After Internet searches we were confident that the symptoms we were experiencing were due to a bad sensor. We had the sensor changed ($$$) During this time we decided to downsize to one car since my husband was deploying and choose to keep his Volvo over my Cadillac cts, we thought the Volvo sensor would be an easy fix and the better/safer car. We sold the cts. Well we were wrong, changing the sensor did absolutely nothing. It is now the most dangerous car because it stalled on me in oncoming traffic. I refuse to drive it, which is hard when you only have one car. The funny thing is now he can drive it and is never stalls, we have taken it on three road trips from va beach to Florida & Louisiana. (Still hesitation while accelerating and obvious fuel pressure problems) but it's only when I get behind the wheel now does it stall. He says he has 'learned how to drive it' whatever that means. He says mornings are the worst but the car gradually runs better throughout the day (as the fuel pressure builds up?) Never has issues with starting. Check engine light remains on. The mechanic we took it to says the code now reads p0090 (fuel pressure regulator circuit) and the suggested we change the whole fuel pump ($$$) he said the gas tank & oil filter are clean. We have no issues with gas mileage. Looking to get a second opinion from someone else.. It seems like these fuel pressure issues run rampant with s60's.... Thank you!!

[jimmy57]

The fuel pump on that car is controlled by a fuel pump module, also known as pump electronic module. The engine computer reads the fuel pressure sensor and signals the FPM/PEM to regulate the fuel pump. The FPM/PEM is on the edge of the fuel tank under car and they can get corrosion at the connections. Can be serviced without removing the fuel tank as it on the right front corner. Volvo has a relocation kit to move the unit into the trunk.
The fuel could be a problem but usually on this system if the fuel pump is binding up the fuse will blow if it does it many times and it sounds like your car has stalled several times.
The problem is worse if driven slow and your husband probably drives more aggressively so it happens to him less. When the pump is run at its slowest speed which is driving slowly and coasting up to stoplights instead of running up to them and braking at the last instant, the connections get hot and the pump stops and it sets the code you have had read out.
Regular fuel did not have any bearing on this problem.

[Brenan09]

Thanks for all the info! So is a full fuel pump replacement necessary?

[jimmy57]

The first thing to check the fuel pump module and its connections.
I think fuel pump is not likely to be the problem.

[Brenan09]

Thank you to you thank you!! Having a mechanic look at that this afternoon!

[Renie21]

Did you know that there is a fuel pump extended warranty on your vehicle? 10 yrs or 150,000 miles