LET Expert needed!

[Adam*D]

Hello everyone, long time no speak
My mate has just aquired a corsa with a turbo lump. It was all running perfect for a few weeks then his problems started. He was driving and it just started running on 3 cylinders. We have changed plugs, leads, dizzy cap, rotor, injectors, fuel pump all thin vaccum pipes. We checked the timing and the belt had jumped approx 2-3 teeth so it's been reset now. Is
this enough of a jump to bend valves?
We have also noticed the knock sensor isn't plugged in as there is nowhere to plug it
Also, in the plastic injector rail wiring compartment there is a cut wire (green with white trace), this has been there all along but the car was running lovely???
Any help as it's really testing our patience!

[Nova_Tek]

Do a compression test mate, will be able to tell you if there is problem internally hence it running on 3 cylinders.

[Adam*D]

forgot to mention that, all 4 are the same 160psi

[Southie]

Have you a eml light wired in?

Have you tried another AFM, they are known for faults.

What plugs have you tried?

Also are the intercooler pipes definitely not split?

Edit:
The knock sensor plugs in here.

[Longdogcharlie]

Ive had it with the wires damaged to the temperature switch and it ran rich on 3 cylinders..

[Adam*D]

The engine is in standard tune, so standard calibra turbo plugs were used.
No EML wired up but we have access to a vauxhall computer, this has told us the ECU was broke , we tried another ecu from a running car and it was the same??
Even on idle it has a slight missfire, but before the new injectors were put in it was 10 times worse.
I/C pipes are all fine.

[Adam*D]

Ive had it with the wires damaged to the temperature switch and it ran rich on 3 cylinders..

How could we test the CTS wiring?

[autoworksnovasport]

have you tried a new ignition amp??

[blue_peg_16v]

Are you sur it's not the tank vent valve plug knock sensor should be on back of block on same loom as icv also

[Adam*D]

When I say the knock sensor isn't plugged in I mean it's fitted to the block, but there is no wiring plug on the loom to plug it in???