Help! Mk1 GTi engine cutting out on WOT

[GRPABT1]

Hey guys/girls I have a problem with the MK1 GTi motor in my sierra. All of a sudden it started to all but completely cut out when depressing the throttle any more than just a little. It will start ok and rev all the way to redline with slight throttle but coughs and splutters and nearly dies if you press the throttle to far too quickly. So far I've changed the spark plugs, leads, rotor, dizzy cap and fuel filter. Any ideas what could be the problem before I get the shits and throw some money at a mechanic?

Thanks in advanced for any help.

[Goatse.AJ]

Timing? TPI?

[joeblow]

they have a shitty idle up control mechanism that sits on the side of the plennum, knowm many a gti to play up because of this.

[GRPABT1]

Timing should be ok, hasn't been touched. And what's TPI stand for?

[lay80n]

Throttle position indicator - TPI

Layto....

[GRPABT1]

Oh like TPS lol. Yeah that's one suspect but I think maybe Air flow meter first

[scooby_74]

Check your fuel pressure, too low will create that prob.
Crimp your return line, that will tell if pressure or injectors are ok.
Bothe TPS and air flow create probs, make sure you dont have an air leak between the air flow meter and throttle body, will cause that prob aswell.

[GRPABT1]

Ok guys took it to a mechanic and it ended up being a loose wire on the air flow meter, I never would have found that myself in a million years lol I hate wiring.