If I have it connected (multiplug on the back of the inlet manifold) my car refuses to start. Fuel pump primes ok but the starter motor doesn't even turn. Nothing. If I then disconnect the cold start injector it'll fire up with no problems at all! Any ideas?!

 

Leave the cold start disconnected!!!

 

Surely it should have it for cold starting? Having said that, it does start ok from cold with it disconnected... Just wondering why the starter doesn't even turn over really?!

 

Yeah thats a strange one mate?! Must be some sort of wiring problem (er... obviously lol ). I'd take a look at the starter wiring first!
It starts without the cold start injector ok because your main injectors are probably leaking whilst the car is stood up and so there is plenty of fuel in there for a cold start (this is the most common reason for unpluging the cold start injector, when really the main injectors should be replaced!).

 

That makes sense I guess. I know my starter wiring isn't the best - the exhaust is waaay to close to the starter, I thought there was a bit more room usually but the cars got a massive s/s exhaust straight from the turbo... Might need to change that, lol

 

lag the exhaust and lag the starter with reflective laggingdid this to mine when i replaced starter
worked a treat