loss of compression/power

Gtirchris wrote:Hmm, you would expect it to stutter if it was a fueling issue, but having said that it could well be a dodgy pump, especially if it has been sat for a few years as the pump may have corroded internally, try a new pump and filter, easy and most likely things first and all that mate.

There is new filter on it and I'm thinking to suggest pump and I'd do straight feed from battery to pump (with all the relays obviously) and honestly don't know if it stutters cos bloody thing always run fine when I'm in it

My first bet would be ignition amplifier breaking down under heat. All my gtir's I have put some thermal paste and a heat sink on them.

Just asking was the bottom end all ok seems to me something tightening up. I think all the above would cause issues sooner than 20 min 40 min drives

yeah agree with above

sounds to me as though some clearances may be slightly out with bottom end and engines getting tight when hot (just a possibility)
once it gets hot and the problem starts if you turn the engine off does it immediately start (crank over) at a normal rate or does it sound laboured when doing so?

Other thing it could be (if mis-fires are present when hot) is an ignition amplifier module overheating.

So depends on the above with regard to engine cranking speed when hot

Riiiight correction car runs ok but after some driving starts to play up when boost comes on (just been informed properly) and when it's playing up starts ok no struggle and it's smooth struggle no missing just no power after 3k rpm

Dodgy maf

GTI-R US wrote:Dodgy maf

I've put known working one on (was on my car for 6 months) I'll see car again Saturday I'm gonna put boost gauge on it and drive around till it'll plays up...
I've put something on fb too (big mistake) and one guy came up with maf plug, need to check it too, and obviously infamous knock sensor which I've got no idea how to test

Knock sensor won't cause car to splutter and die at 3k but it will drop boost to around .6 bar and pull around 2 degrees out of ignition from mid range to wot which will cause the car to feel sluggish and gutless. Timing is advanced when engine is cold so won't be so noticeable with power loss

Best way to test it is to put + side of multimeter on the pos side of sensor and the other side to earth, set meter to ohms and you should have a reading of no less than 5.58 megaohms if it reads less then good bet that the knock sensors knackered

I just love to chase intermittent faults   I shall know some more Saturday...