Hi all, my car seems to keep going into 'limp mode' as I hit around 80 mph and at certain revs.. turn the engine off and on again and it will clear it, the emission control light came on when this happened.. I've changed the maf sensor so that's one diagnostic covered.. any help much appreciated! 

Sounds like the turbo boost regulator being a bit sensitive....sometimes if it kicks in on overboost situations this can be down to clogged up vanes in the turbo....maybe run some cleaning additives through the engine/turbo and see if that improves things

 

Thanks mate, what could I use and how to use it to clean it? Cheers, I'm quite new to this 

You could try this one 

http://www.ebay.co.uk/itm/Diesel-Engine-Turbo-Cleaner-Cures-Limp-Home-Mode-Variable-Vane-Turbos-/152003334878?hash=item23641ad2de:g:lQ4AAOSwZ8ZW2O4l

Otherwise, there are some posts on here about cleaning the turbo vanes and Mr Muscle or similar has been suggested to use (cheaper alternative)

Thanks for your help mate

try the Exhaust Re-circulation Valve (EGR) located at the intake manifold at the front of the engine. it might need cleaning.