At Bedford Autodrome on saturday, towards the end of the day, Alex was driving when suddenly the engine died and wouldn't restart. We had to get towed back to the pits, then back to the trailer. So glad we didn't drive to the track.
Symptoms:
Fuel pump primes
Starter will run, even without the immobiliser dongle ( Sterling Excel )
ECU checks out OK over USB-CAN interface
Must be ignition
Work down the fuses, a 15A is gone - must be ignition
Replace fuse, blows on start
Pop the engine cover off, inspect loom
At this point I found a short to ground where one ignition signal wire has rubbed through insulation on an unused threaded post. So I reinsulated the wire with self adhesive heatshrink sleeve and wrapped the bundle with protective loom tape. Then I secured the bundle with a P-clip to the offending post.
So the engine starts again but only on 3 cylinders. Seems number 2 coil-on-plug unit has ceased to be. The others are 0.8 Ohm, no.2 is 0.4Ohm - I'm thinking coil meltdown. Ordered a new one from CC this morning, should get it tomorrow. CC are cheaper then local Ford and even eBay on the CoP unit, so good for them.
For ref, the CoP is a 4M5G-12A366-BC
Fingers crossed this is the only problem, though I'm pretty confident. I thought it might pay to write this up and caution anyone with a similar vintage duratec to have a quick look under the engine cover and check there's no chafe damage. If the engine had stopped while I was cornering, it could have been a proper off. Luckily Alex currently leave quite a safety margin between her and the ragged edge. Me, not so much 😬