I purchased an 04 XC90 used in February of last year. Things were fine for the first 4-6 months. On our 2nd road trip after about 2-3 hours in the car at speeds of between 70-80mph the car jolted, like it was a blown tire. I pulled over it was fine, so I thought nothing of it.

On the way back however the car did it in excess of 22 times on a 300 mile trip. Sometimes loosing complete power. We took it to a dealer on the way home. No error codes or anything to explain why the car was doing what it was doing. While at the dealer and trying to accelerate it was like the car had reduced power. Almost as if you were trying to brake while accelerating.

When we got home and took it to the dealer they ran the computer and nothing. The head tech said it may be a loose connection on an aftermarket trailer hitch. We completely removed that. That still didn't do it.

Another trip this week at night and it starts shutting down again. I didn't loose complete power this time. I lost - all internal instrumentation and lighting, turn signals, hazard lights, radio, A/C. I had: brakes, headlights, tail lights and the 12v adapter functioning.

In September of this year I had to have the shift cable and key cylinder replaced. This was done locally as our nearest dealer is 45 minutes away. Could it be something here? I'm pretty sure it did it before the shift cable and key cylinder were replaced but I'm not 100% sure.

ALSO, sometimes it takes a little long to start and runs rough while idling. I'm told the A/C compressor needs replacing. It howls like a banshee. The dealer said it needed to be recharged so I paid for that...Twice, and it is still so noisy it's hard to bear.

Any help would be greatly, greatly appreciated.

 

My guess would be the fuel system. Either a clogged filter or a pump going bad. This would go along with your symptoms and also would not show up on the computer. In order to determine if it is a fuel pressure/delivery issue, the mechanic needs to hook a fuel pressure gauge into the system and tape it to the windshield so he can test drive and monitor the readings when the car begins to act up.

BTW, how many miles on it?

 

Johnny,

It's got 67,000 miles on it. The thing is, it usually only acts up 2-4 hours into a trip. It has only done it around town once (less than 30 mph)
Thanks so much for the advice!

 

Have the mechanic hook up the gauge and make sure it's safe and will not leak or rub anywhere and if it don't act up on him, agree to drive the car with the gauge attached. You can monitor the gauge and see where it normally runs, but when the problem starts to occur, then see if the pressure is dropping.

 

Will do. Thanks so much.