hi i have just been finishing putting my s1 together however when i start it it runs then stalls after about 4 seconds, you can rev it but it just dies like a lack of fuel. i have changed the metering unit for one that came of a running car, i have also tried a different ecu, and spark module, it has the correct fuel pump relay and ignition relay.
the only i can think of is low fuel pressure from the pump, as when you turn the ignition on it primes as it should but then sound weak when the car is running or could a poor earth or live connection in the wiring loom cause a problem.
also it could be a vaccuum leak however normally you can rev the car and it stalls when you let of but this just dies after 4 seconds
could the auxiliry air device or any other sensor cause the car not to run

any ideas or help would be greatly appreciated thanks in advance