320d se Power issues at lower revs
Sorry if this is not in the correct forum, this is my first post. Just after some advice.
The car is a BMW 320d se, 2003. I've had it for two years and it has done approx 130000 miles.
Last month I got the car serviced at local garage, they advised at the time that the air filter needed replacing as it was black, strangely the same thing was said last year aswell when I got the car serviced.
Since I've had it back it's been gradually getting worse in terms of performance in low revs.
Start the car, put it into first and start to pull away only for it to reach about 10 mph quite happily then stop accelerating. The revs won't pick up even if I put my foot to the floor, infact that usually makes it slow down and I have to almost coax the revs out. Once it does pick up I get the usual whoosh and the car accelerates as it normally does.
Following on from this it can seem like it is working normally in 1st but when I change to 2nd it doesn't accelerate, but does eventually very slowly usually until the revs reach about 3000rpm then whoosh again. This can happen in any gear, I can be in 6th doing 70+ put my foot down and nothing.
Now I can drive for 80 miles and experience no problems, but today I went on two 2 mile trips and had to almost fight for every inch!
This all seems to have started after my car was serviced.
Now the engine management light has come on yellow, it has done this before on 3 occasions but has gone after 1 or 2 drives.
I don't want to jump to any conclusions but i am a little suspicous that this has happened after I had the car serviced.
Any ideas what maybe causing the problem, i'm not really a petrol head but if it's a loose connection I can probably sort it myself.