Hello. Have some trouble with my UT 1.4 after having it rebuild. change all gasket, timing belt and bearings, and fitted a Piper fast road cam. everything else is the same before rebuild.
But when I start it up now it's hard to rev the engine, idle is pretty fair. It's no vacuum in the engine, turbo spinning and make boost at idle, not much, but enough to not open the pop off valve, the bosst is comeing back trough the airfilter when I let go off the throttle.
Have checked timing and it's spot on. checked wiring, checked the sensor on crank and flywheel with oscilloscope, they are correct to.
Somebody have any ide what the problem is?

Thanks

It does really sound like valve timing.

oki. thanks for reply. but it's spot on at the marks, but since I have piper cam maybe it's different? does the UT break the valve if it the timing belt snaps? so I can try moving it one tooth? forward og backwards?

tried one tooth back on the camshaft. and it fired up pretty much like normal.. so now I going to buy a adjustable cam vernier..

thanks for help..