cdti 150 tuning box question

[dave r]

hello chaps just after a second opinion , Ive been runing a well known tuning box for the last couple of weeks ,and seem to be having a strange problem .
The problem is after about 20 minutes of driving my car i start to lose power , and the more i drive it the worse it gets. its great first drive of the day but as soon as its warmed up I really notice the power loss .
spoke to the guys of the tuning box company they said my MAF sensor is on its way out thats why im loosing power ,this does'nt make sense to me because when i remove the box it runs great .feels like im getting fobbed off any info would be really helpfull so i can ring them back cheers dave..

[ronnie63]

some of those tuning boxes do not switch on until engine is warm! sounds like it might be faulty to me, as in lowering fuel pressure instead on increasing

Ronnie

[RobW]

They could be right, the tuning box will be putting more fuel in so it will be needing more air and I am sure there is logic in there somewhere?