hello people

I have aproblem with my daily runner which is a punto gt turbo not an RS i know, but hope you dont mind me askin for help as you all seem to know what you are talking about!

i recently fitted a SEB0 chip to the car and its been absolutely wicked - power when you need it, pulling like a turbo up the revs nicely, general drivability etc etc....

the other day, i was on a wet road pulling away hard - one wheel spun up, and before i realised what was going on i was up near rev limiter territory....only in SEB chip world, i dont actually know where that is! I know its raised slightly, but after i accidently reached what seemed to be the mechanical rev limit of the engine, it has not been the same.....

immediately after it wouldnt accelerate properly on boost, although it was boosting fine according to the gauge. I left it over night, filled up with fuel and it seemed like 3rd gear onwards under about 3/4 to full load it pinks initially, then pulls but not as hard as it should, then holds back a bit then goes then holds back etc.

My mixture gauge says its nicely rich, although its only narrowband, and it does react quickly when you alter the throttle etc, so if it were fuel related, surely it would show up on the gauge? eg: fuel pump not coping with 1.2 bar boost anymore....

so what causes pinking or detonation:

hot plug tips/cylinder temps mainly caused by weak fuel mixture or icorrect ignition timing
spark plug rating too hot
high ACT's
high compression or carbon build up in cylinders
very heavy load eg: going uphill, full throttle, wrong gear
water in cylinders (head gasket failure)

But how would high revs, that are presumably safe to hit once in a while due to the rev limiter being raised, cause this pinking and lack of power? By the way the chip i ahve fitted has been used in thousands of other puntos, and is written by a good italian tuning fella i have heard anyways, and although the chip is effectively a stage 1 generic type chip, its not like superchip as its meant to be by this italian chap who knows his potatoes!

the engine runs fine as far as we have checked it so far - the boost has been turned down a little to see if that helps, oil level, condition and pressure is good, coolant is good ie: not contaminated or low like its leaking into cylinders, block tested for head gasket = good on tests lasting 20 mins per test. Cat test shows MOT perfect on all gasses. Its also running only 8 HC's!! Plugs have been changed as a precaution and are the same NGK BCPR6ET's as before, so the heat rating surely cant be wrong all of a sudden?

I did think maybe leads and coil pack may be breaking down, but if this were the case, it shouldnt pink.

I doubt veyr much that its any kind of mechanical failure, but im not ruling it out completely - there are no knocking noises what so ever and the car drives as normal until you start to try and boost hard. It still goes pretty quick but although the boost is there it just doesnt pull like it did. Its also best to nip pinking/detonation problems in the bud before they cause real damage.

any help or ideas much appreciated - sorry for the essay!

Thanks