2006 XC70 Road trip madness!

Post by **IVIUSTANG** » 31 Dec 2013, 17:48

Hi guys, I just drove my XC70 7000KM in the past week on vacation.

It did excellent in the snow. My problems started when I got into a warmer climate near Las Vegas, after crusing at 85MPH for hours on end I pulled over for gas and my car would barely idle; I limped it in to a gas station and checked for any codes, there were none. I topped it off with fuel and went on my way symptom free.

I drove another 5 hours with no issues, once I arrived at my destination the check engine light finally came on. It was showing P0089 Fuel Pressure Regulator - Performance; I did a bit of research and found the most likely culprit on these cars is the fuel pressure/temp sensor on the fuel rail. I replaced this with a Bosch part and thought I was good to go. I drove the car the next day for about 3 hours in hot and heavy traffic, after bucking for a few second and coasting to a stop on one of the 7 driving lanes(LA rush hour traffic no less) I let it sit for a minute, unplugged the fuel pressure sensor and plugged it back in. The car was now idling normally and had good power, so I limped it back to the hotel and did some more research. My car was now throwing P0300, P0304, P0305, P0089 plus a few other fuel related codes.

The next day I drove my car to "Volvo Pitstop" in the Burbank area, he hooked my car up to his Dice and saw that my fuel pump was idling at 42% load when fully warmed up; he said it should be around 35% + or - 5% I had read this before so I said to go ahead with changing the fuel pump. He showed me that the new pump was idling at 35% now so I was happy.

He put in a Volvo fuel pump, fuel filter and I also asked him to to drain and fill the transmission. When I picked it up, everything seemed hunky-dory. I drove it back home the next day.

About 5 hours into my trip I did an aggressive pass and as soon as I pulled in front of the other car my car lost all power and I had to once again pull over. The idle was fluctating between 500-1000 very smoothly but had no power; "reduced engine performance also illuminated on the dash. I turned the car off, scanned for codes(there were none) started the car up and the car has literally ran perfectly for the last 30+ hours of driving since then. The "reduced engine performance" is still on the dash and I can't clear it with my standard scan tool.

I know I have given a lot of background information here but thought it relevant.

Sam at Volvo Pitstop said he also reset the transmission fluid "counter" back to zero.

Does anyone have any possible explanations for the stall AFTER the fuel pump and the "reduced engine performance message?"

Also note in the past year I have changed all plugs, and all coils.

Thanks for the help!
Jesse

Post by **jimmy57** » 31 Dec 2013, 18:58

The connector on PEM (AKA fuel pump control module) should be checked. Those can get overheated on the pin for power out to pump and sometimes on power in terminal. Water ingress is the likely culprit and corrosion can be an issue too. The unit is on right side adjacent to forward control link for rear suspension in the vicinity of fuel tank.

Post by **IVIUSTANG** » 02 Jan 2014, 08:41

I've checked the PEM connector it looks clean. Anything else I should be considering here?

Thanks,
Jesse

Post by **jimmy57** » 02 Jan 2014, 09:25

Let's not assume fuel pump issues. New pump and good PEM connection may rule out fuel pump as cause.
Get VIDA-DiCE read of the codes so the problem as ECM defines it is understood.

IT could be bad PEM but those are rare when no pins and terminals are damaged.
I have heard of PEM water intrusion. IS the PEM clean or is that area full of dirt and mud build up?

Post by **IVIUSTANG** » 29 Jan 2014, 21:18

PEM appears clean, the check engine light came on tonight; one month after the fuel pressure regulator, fuel filter and fuel pump were replaced. The code that came up is P0089 Fuel pressure regulator performance! I am getting so fed up here, anyone have any other ideas?

Thanks,
Jesse

Post by **chrism** » 30 Jan 2014, 06:53

Do the problems increase as the fuel tank level drops? I'm thinking a possible fuel pickup/starvation problem. At this point I think I'd connect a pressure gauge to the rail and tape it to the windshield where you can monitor it while driving under load.

Post by **IVIUSTANG** » 30 Jan 2014, 08:52

Doesn't appear to have an issue with a low tank, yesterday I drove the car till the gas light came on. No issues; I then filled it up and drove it for 3 hours, then the P0089 illuminated. A sent an email to XeModeX last night and they responded that they definitely think I should replace my PEM based on the issues I've been having; what are your thoughts on this?

Thanks,
Jesse

Post by **chrism** » 30 Jan 2014, 10:57

You may very well be right. But it would be hard for me to shell out the $300 on a "maybe". Although the codes almost surely point to a fuel system issue, if you had a pressure gauge available it wouldn't hurt to test it. Sometimes the auto parts stores have specialty tools like that that you can check out for just a deposit. At least it would give you a warm fuzzy feeling that you are in fact chasing a fuel delivery problem and not something else.

Question - when you checked the PEM connection, did you check the plug at BOTH ends of the "adaptor" (as Volvo calls that short wire harness)?

Do you have any wrecking yards near you that may have one? Or maybe try someone like Southern Vo-Vo. I don't know if the PEM is something that you would want to purchased used or not. Maybe not.

Post by **IVIUSTANG** » 30 Jan 2014, 11:52

The freeze frame data for the P0089 code listed the fuel pressure at 54 PSI at 1800RPM; and $300 is nothing for me to throw at this problem at this point. I do like that the XeModeX is waterproofed better than the stock as well. I have done river crossing and high speed puddles in this car, and I have bogged it up to its gills in muddy water requiring a winch out. If water intrusion is supposed to happen to anyone it surely is my turn! I have only checked the one connector at the PEM. I'm pretty sure I can view live fuel pressure data with my OBD scanner, it's a good one; of course it's only as accurate as the fuel pressure sensor.

Jesse

Post by **chrism** » 30 Jan 2014, 14:05

You're way over my head - I'm old school. Good luck!