Hi,
Just returned from a 2800 mile round trip road trip in my '06 Volvo xc90 2.5L 5-cylinder AWD turbo (130,000 miles). Twice during the trip while driving at high speeds on the highway I experienced a sudden loss of acceleration. The car continued to go, but I couldn't get any acceleration. RPM's dropped to under 2,000. Feels like the turbo cut out or fuel wasn't getting to engine. One time I was going uphill and my speed dropped from 70mph to 40mph before the acceleration returned to normal. Each time it lasted for a few seconds then the acceleration would kick in again and the car would work fine for another 1,000 miles or so. Both times outside temps were 90+ degrees and A/C was cranking. No warning lights or service notifications came on. I didn't notice any unusual sounds. Both times the car was down to about 1/4 tank of gas. Any suggestions of what the problem could be? I had the car inspected and oil changed before the trip and told all looked good. Thanks!

 

This happen to me once before my no start condition, no codes. Have u been in a rainy area prior to this? Fuel pressure regulator?

 

No rain for at least a week before the trip and none during the 2 week trip.

 

My guess is your PEM starting to fail if its located by the rear passanger tire or fuel pump starting to go bad, only way to I know to make sure is to hook a fuel pressure gauge and drive around with it to try to replicate the problem sense u got no codes.