Mk1 1.6 Zetec SE Cold Start fault

[daston]

Hi guys, 

My our Mk1 1.6 is driving me nuts! It has recently developed a issue starting when cold. The engine will crank but not fire (although it sounds as if it does at least attempt to try). 

I have checked the following:

HT Leads deliver spark

Fuel Pump primes and delivers fuel (that was fun)

New fuel filter fitted

Diag reader finds no error codes.

The engine will run if I squirt carb cleaner into the intake manifold, once started I can then shut down and restart with out any problems at all. The car also seems to behave itself once running, no rough idle or stalling. 

Any ideas? Plugs looks a tad black so not enough spark from cold? Dodgy coils? or something like a camshaft temp sensor not putting enough fuel in when cold?

Any help would be amazing 🙂