I posted this in the General section and only got one reply, so I thought I'd try here:


'All' I did was remove then replace the headers (after removing the heat shields and associated lugs, porting them and then wrapping them) go back to the standard up-pipe (again ported and wrapped) change the turbo for another TD04 (i.e. the same size), wrapping the down-pipe and re-fitting of the turbo heat shields after cutting them to fit the new dp.

I then had issues with the steering, but that's another story!

The latest problem is that when you put your foot down (i.e. press it down 3/4the way and keep it there) the turbo spools up, then drops off then spools up again etc. all the way through the rev range. It's a bit annoying to say the least!

Do you think that I could have a leak in the turbo pipes etc?

A guy checked the actuator for me my applying air from an air line to it and it opened cleanly and fully.

I have also since replaced the MAF sensor as when I did an ECU diagnosis code 23 came up! This cured the problem where it was ticking over lumpily and stalling occasionally.

Any ideas?
Other than "don't mess around with it in future!!"
The car is a UK spec MY00, running full decat, ported headers and up-pipe with replacement K&N filter element, other than that engine performance wise it is standard.

Thanks in advance!