Rough engine when A lane turned off

[GerryWA]

I believe we have an ignition problem - seems to be related to temperature. Do our runup when oil hits 120, with A lane off engine runs rough and fails rpm drop limits. We swapped connectors and problem follows to the B side. Its interesting that if you keep engine running and heat oil up to 170 to 180 the engine check cleans up, not perfect but within limits. We removed ignition modules today and plan to send them both to Lockwood for testing.

Anyone seen this temperature based behaviour? 380 hours on engine.

 

[Amadeus]

I believe we have an ignition problem - seems to be related to temperature. Do our runup when oil hits 120, with A lane off engine runs rough and fails rpm drop limits. We swapped connectors and problem follows to the B side. Its interesting that if you keep engine running and heat oil up to 170 to 180 the engine check cleans up, not perfect but within limits. We removed ignition modules today and plan to send them both to Lockwood for testing.

Anyone seen this temperature based behaviour? 380 hours on engine.

Experienced this just once and it was shortly after doing my annual condition inspection. About two weeks after. Turned out that I did not get a spark plug wire pushed on firmly and it eventually fell off during flight and noticed on next run up.