Bad tick over and no boost

[s2tommy]

Hi everyone. Right I have got my s2 up and runnin but and there's always a but! Very poor tick over, revin up an down and sumtimes cuts out. So I have done:
cleaned maf, was much better now but still messin about an cuttin out from half throttle to idel.
changed idel valve, no difference
changed brown sensor in manifold, better again but revs going up am down on tick but not offen but still cutting out
I think in my eyes that the return punger on the throttle body may be to weak? Goin to change that 2 moz nite. But other wise once off tick over revs lovely.

And also it's like it's stuck in limp home mode because won't even spool up properly and only gettin 6 psi. Now I have been told that the pipe on thr n75 valve which goes into the standard intake pipe between maf an turbo can be left out without connecting it to anything?? As I have had to make custom pipe work.

Engine spec
je custom 82mm pistons
eagle hbeam rods
arp top an bottom
muti layer metal head gast
3b fly wheel
034 race coils
standard aby intercooler but only at mo
5 branch manifold with hybird kkk 26/27
ecu had 280 chip before rebuild

car always mucked around with boost before rebuild, if I was town drivin and engine temp got around 80 just over then I would get 6psi but then went out of town onto the wide open roads 1 or 2 miles temp would drop to about 60 ish an off I wud go 22 psi just like fickin a switch

any ideas wud love to hear. Tryin to get her on road for 1st of next month
cheers tom.

[JP]

Pressure test the boost run sounds like you have an air leak. The bad idle will be from unmetered air being fueled/not fueled for. And lack of boost is due to the fact the system can't hold pressure.

[prj]

6 psi sounds like limp mode in the turbo chip or incorrectly connected/malfunctioning N75.
Doing a leak test, as suggested by RWD19T, is also a very good idea.
Rough idle can also be caused by a malfunctioning oxygen sensor/MAF, but unmetered air entering the engine is more likely.

Does the car throw any codes?

[Rusty]

As above. Dirty MAF & TPS unplugged is a good one to check too.

[Jamo]

Sounds to me like the timing isn't right, how did you time the cams / cam pulley?

[s2tommy]

Done maf
changed sensor the brown one in maifold by throttle body
changed idel valve
put new seal in intercooler where it meets x member
double checked all pipes from turbo to inlet manifold
all in good con
will try an do boost leak test an goin to get friend to come plug his vagcom in to see wat it says
did have cams out of head and was shown how to refit. How I was told is there is a dot punch hole on each cam. As I looked at the front of cam wheels had the exhaust cam dot at 3 o'clock level with top lip where rocker gaskit sits and the inlet at 9 o'clock same siting level with lip and both dots level with each other and level with rocker cover lip and tighten cam caps the dots did move alittle bit once tighten down. Once I rev it **** hair off tick over runs sweet as a nut right up the rev range no bangs or rattles. Starting to get to me now!

[GazzaG60]

compression test?

i had similar and it was a broken cam. mine ran worse though.

[Jamo]

Done maf
changed sensor the brown one in maifold by throttle body
changed idel valve
put new seal in intercooler where it meets x member
double checked all pipes from turbo to inlet manifold
all in good con
will try an do boost leak test an goin to get friend to come plug his vagcom in to see wat it says
did have cams out of head and was shown how to refit. How I was told is there is a dot punch hole on each cam. As I looked at the front of cam wheels had the exhaust cam dot at 3 o'clock level with top lip where rocker gaskit sits and the inlet at 9 o'clock same siting level with lip and both dots level with each other and level with rocker cover lip and tighten cam caps the dots did move alittle bit once tighten down. Once I rev it **** hair off tick over runs sweet as a nut right up the rev range no bangs or rattles. Starting to get to me now!

What about the flywheel? was it at TDC when you did this and did the came wheel also line up?

[prj]

You should definitely first check with vag-com before swapping random bits around... quit wasting your time.