Mk1 Focus 1.6 won't start - engine light on

[Daston]

Garybee said:

Didn't mean to leave you hanging. As it started quickly with the carb cleaner you know the problem is with the fuel system and everything else is fine. It's not odd at all that it starts straight up 2nd time, that's exactly what happens when the system fails to hold pressure in the fuel rail. The system on a mk1 focus runs a return rail back to the tank so there are 2 [likely] ways you can be losing pressure:-

1) The pressure regulator (sits at the return end of the fuel injector rail) is leaking pressure into the return line to the tank.
or
2) The 'Non Return Valve' (sits after the fuel pump) is leaking and allowing pressure to be lost back through the pump into the tank.

To confirm you're going to need a fuel pressure gauge. The Focus has a schraeder valve on the fuel rail which makes the test very easy.

Thanks, I will give these a check.

[Dr Doofenshmirtz]

Be careful here - Our Focus had exactly the same symptoms you describe, but really unhelpfully I can't remember what I did to fix it?
I think I took out the coil pack, changed the spark plugs, swore at it etc and it worked fine afterwards and ever since...
But anyway - all that cranking and coughing and sputtering must have shoved unburnt fuel into the cat knackering it and I had to replace it (although it was pretty cheap at around £50 iirc).
The speed sensor is a right bh to replace - there's a pin holding it in which is a real pain to get out. It was a horrible job. It wouldn't affect the car running though.

Good luck.