Well we have put 23,000 miles on our 2001 S40since we bought it last June, it only came with only 50k miles so we've added almost 50% more miles but it's been great. The past couple weeks however we have noticed that when driving at slow speeds in the morning, sometimes the engine is hesitating a bit or feels like it lacks power, but it's fine once warmed up.

Then the past 2 days it has been cranking without turning over for much longer than usual. Yesterday I had the battery, starter and alt tested and battery was low (it was the ORIGINAL battery) but starter and alt fine. We put in a new battery and figured we were done, after all it did recently get cooler here and rain - usually the death blow for a low battery. Went home, parked, had dinner then went out an hour later and the same thing happened - crank crank crank then start finally. SO it wasn't the battery, or at least it was not just the battery.

So today I took it back to the garage near my work (not a Volvo specialist but has done good work for me in the past). THey didn't have time to look at it after it sat there all day (fair enough I was a drop in, but waste of a day when the car could have been getting fixed). I put a new air filter in it too because the old one was due for change and it was dirty, thought maybe it was not getting enough air - but that didn't help.

I have noticed that fiddling with the gas pedal - giving it a quick tap - seemed to help.

I suspect this is maybe a sticking throttle body or something? Any other ideas?

Thanks!