Ignition problems Legacy 2.5 NA 1997

[Steve_D]

Engine starts to run rough then eventually won’t run at all. Pull a plug lead and there is a spark to the block. Pull the plug and hold it against the block there is no spark at the plug gap. Hold the plug away from the block and the spark jumps across but still no spark at the plug gap. Increase the air gap and eventually the plug will start to spark at the gap.

Conclusion duff plugs.

Fit a new set (expensive) and after ten minutes the same happens. Engine was not happy when on the fresh plugs so I knew this was not going well.

First set of plugs were quite new BoschFR5DPP222 second set NGK PFR6B.

Thinking perhaps the coil was duff and allowing the plugs to foul so it was replaced.

Thinking the Ignition ignitor may be the next culprit but there is little info on what it does exactly. The fact I have a full set of sparks may be proof enough it is working or is it supposed to amplify the spark? Further investigation seems to indicate they are not readily available and it was inferred to me that was because they never go wrong.

The engine is in a Kitcar but has not thrown any relevant codes.

Any ideas what is going on?

Many thanks
Steve

[Steve_D]

Konan said:

Have you been able to measure output from the ignitor?

I have the full manufacturers handbook but it does not offer much in the way of testing the ignitor unless I have an oscilloscope so no not been able to test it.

Steve

[Steve_D]

The Handbook shows what I think was 2 transistor symbols which I don't understand as I was expecting it to be more complicated than that.
Also, if it is just 2 transistor circuits then why would both circuits fail unless there was some other common circuitry.

The coils seemed to be firing in the correct order/rate and yes they are wasted spark.

Steve