Noble part 2

This car has proved difficult to diagnose, an intermittent miss fire, normally under load had proved elusive. Weather conditions, lack of rolling road time, along with fixing other basic problems had turned this into a bit of a saga.

Having checked the inputs/outputs of the ECU, everything appeared fine. However the car would occasionally cut out. Once this happened it would re-start and perform without fault for ever decreasing amounts of time. The ECU was inspected and tested and was found to be ok.

I turned my attention to the coils, these showed good current ramping (below), but it was during these tests the car cut out. The output just vanished.

This means the ECU has stopped grounding the coils, but why? Could it still be an ECU fault?

I decided to investigate further, a check with the local Ford parts department proved fruitful.

The coils have been super seeded.


We tried a new coil to see if there is any noticeable difference. The current trace (above) shows the subtle but measurable difference. A further 5 coils were ordered and the car returned to the rollers. We now had closer to the rated output and no miss fires!