I have a 2004 S60 with 79,000 miles. It runs great, gets around 31-32 MPG on Highway. The only problem is it skips when accelerating quickly, like coming on to an interstate, passing another car, etc. Any ideas about what to look for first?

My '01 V70 would run fine except during heavy acceleration and it would stutter, skip, shudder,miss, not sure how to describe it and very noticeable! Turned out to be a coil pack. Under normal driving condition car ran great and no symptoms. Fuel mileage was spot on, just under hard acceleration. Check engine would flash, but would not store a code. Finally, found a big long hill and manually shifted the auto trans in 4th and from a slow speed was able to keep the condition happening long enough to set the code. Got a misfire on a certain cylinder. Moved the coil pack to a different location and repeated. Got the code on that cylinder. Replaced it and problem was gone.

Keith

..If you mean a "hesitation" within the same gear, then I recognize it as a "problem" (I can live with) I have with my S60 NA 2001 since new. A few software upgrades have improved a bit, but it never completely disappeared.

Since you have a newer model, you could think of the Electronic Throttle Module - cleaning might help (next to the spark plugs KlausC is suggesting)..

When wer the spark plugs last replaced? Is this a turbo or NA engine, it makes a big difference.

Next time you give it throttle, try down shifting first to get the rpms above 2000 and see if it happens again. The trans might currently be trying to down shift at the same time as throttle up.

Klaus
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