Excellent, thank you for the advice. I'll start there, will update once I've checked it over.

Thanks, I'll have a check of the pipes. It's a Diesel engine.

First post so be gentle :P (I did do a search but didn't find anything). Hi, I have a 2006 BMW X3 M Sport Auto and noticed recently the gear change is very laggy. Also took it on the motorway and it seems to have lost power, doesn't want to go over 3K revs and takes an age to get there. Any ideas on ...