I've got a 1999 S80 T6 that drives fine under a light load but stumbles from 2000-3500 RPMs. It also surges occassionally while accelerating moderately. The check engine light flashes when this happens and it has stored several codes. I had them read at Autozone but I don't think their print out is correct for Volvo.

P0201 - Fuel injector 1
P0206 - Fuel injector 6
P0300 - Misfire random cylinders
P1238 - Fuel pump secondary circuit failure

I was searching around the site and saw P1238 mentioned as the TCV (turbo control valve?). Any info or help would be greatly appreciated. Thanks!!

 

P1238 in a Volvo is the TCV. Not sure what you should do with the injector codes. Start by cleaning the TCV, worked for me. Remove it and exercise it with 12v, polarity doesnt matter. Clean it with carb cleaner, be sure to dry it out before putting it back in. Worked for me, 800 miles so far.

Also check all the plumbing right back to the wastegate actuators.

 

yeah hold off on the injectors, not sure what the TCV is gotta check vadis, but do what boost said and report back, other codes may be triggered but this TCV...

 

Check your coil over plugs. They sit right on top of the spark plug. You can check this by disconecting one of the coil packs, tuning the car on, and seeing if it sounds worse or the same. If worse then it is not that coil pack. If it is the same then it is that one. I had to change all of mine out at about 101k. It also told me a random miss fire and a bad tcv. Wasn't the tcv till later. Coil packs run about $50 for sone auto zone ones. Napa caries the ones made by volvo.