52 plate C220 Auto
 

Hi. I have a bit of a problem, when I first start my car an put it in reverse their is no power at all when I put my foot on the excelorator, the revs stay on idol (900 revs) even if I put my foot right down. It also not responding straight away when I excelorate takes maybe 1-2 secs to respond. I have also just started getting the smell of fumes into the car, which is coming from the back of the engine. I've had the car for 4 weeks an the problem is slowly getting worse. Any helpers please. Been told it just could be the oil that needs changing.....:(

Not sure who told you just to change the oil but I would probably not seek automotive advice from him again. Is the check engine light on? Do you experience lag when taking off in drive? If you do, it could be the mass air flow sensor.

no light on. an yes i do get lag

Then I would put my money on a faulty mass air flow sensor

I have just ad the cover off, an at the bass of the injector, it is blowing air out. So do I just need to replace the the injector or just the seals

You can try just the seals first as it is the cheaper option, if that doesn't work then the injector should be replaced. Check for cracking where the injector sits when you have it out though.