Thread: loss of power

i have a seat leon cupra remapped,when im accelerating keep getting a momentary loss of power then it kicks back in again jerking the car forward,or when im motorway driving it keeps pulling then easing off like it has a mind of its own.no engine lights coming on or anything.any ideas,only started happening over last few months,remap done back in march and have no probs with it until this

Originally Posted by pakmoto

Sounds like the MAF sensor could be at fault, is it petrol or diesel and what year model?

it is petrol on a 53 plate,ive had a diagnostic done and is not showing up any sensor faults,im thinking it may be a split in one of the hoses,boost leak?

Originally Posted by pakmoto

Im assuming you have tried a full service (plugs, leads, oil and filters etc)

A boost leak would not be intermitent as you describe

Also a MAF sensor doesn't always show up on the ECU codes.

just had service done,i would say prob is always there,3000rpm range and also when accelerating hard or doing mway driving at 70-80.is maf sensor expensive to replace?

I have a similar problem with my Seat Leon 1.4, 03 plate. I bought mine around the end of August/beginning of September. A couple of months ago my Seat lost power several times on my short journey to work – battery light came on, didn’t hear the car cut out at all (radio continued working), steering wheel became stiff as did clutch pedal. This shook me up quite a bit. I phoned the company I’d bought the car from, they recommended I get it to a mechanic I know who did a full diagnostic on it. It turned out to be a faulty temperature sensor. This was replaced around the same day.

I’ve since had another, unrelated problem with the car – a cracked sealant somewhere underneath the dash that was letting water in and absolutely soaking my drivers side floor. Again this has been sorted.

I thought the loss of power in my Seat had been resolved but this morning on the way to work as I was slowing down to stop at a junction the battery light came on again, the car went into a sort of drifting mode and my clutch stiffened up. I was not required to turn my steering wheel at this point as the road was downhill but straight so don’t know if the steering wheel went stiff as well. The only way I’ve been able to resolve this problem is by turning the key in the ignition towards me (so into the off position) and then turning it back on again. If I turn the key away from me to simply attempt to turn the ignition back on, the key does not move hence why I have to turn it off completely before turning it back on again.

Surely this can’t be related to the temperature sensor again? As a female driver who’s young (25) and only been driving for 4 years I’m finding it really quite scary.

Has anyone got any possible solutions for this?