mkIII won't rev!!

[whyme]

Hi, my mkIII single turbo starts first time but will not rev. I have relocated the air mass meter but it is still in the air flow only difference is it is now mounted in a section of the rubber pipe instead of the original hard plastic casing. The only other mods were larger inter-cooler, turbo rebuilt, complete exhaust system and air filter. Fuel pressure and spark seem to be okay. The engine management light does not light at any time. Do any of you guys have any ideas.

Thanks,