Any ideas?, I'm losing power and it misfires/pops at around 3k when the turbos starting to kick if i'm heavy on the go-fast pedal, but if I gently increase the revs, it'll go past 5.5k with no problem !
Thanks for that, is there anything visually that I should look for when I pull the plugs ?, or will they just look knackered ?. Seems weird that under gentle acceleration, the car's ok. Though at first might have something to do with turbo pressure. Does the car measure it?, if so where and how ?
No it doesn't measure the boost pressure - but if the spark is weak for whatever reason then at mid rpm - high load conditions (wide open throttle) - the spark will struggle to ignite the mixture. At high rpms the mixture is more turbulent and more easily igniteable so wider throttle openings can be used without the stutter/misfire.
A bit like someone with a dicky ticker - they might might be able to manage a 10 mile slow walk but a 100metre sprint would put them in the hospital.
This may not be your problem - check for any boost leaks too (after checking plugs/coils/HT leads)
- loss of air will screw up your mixtures and can cause misfires if extreme. Check all the small vac/boost tubes especially - it's easy for one to be split such that you can't see the tear.