Had Missfire For A Day, Now Gone?

[ms33]

Any of you guys had an unexplained missfire for such a short period? Started yesterday so checked resistance in coils...ok. Checked sparkplugs..seem ok, are new though. Ran ecu diagnostic, no errors logged, checked lambdas..ok.

Then today, went for a run, still missing, especially at higher revs then after an hour, totally went and runs perfectly again.

Any other thoughts on what it could have been??

[Hanaldo]

I sometimes get a similar thing mate. I think it is from having a very rich tune on full boost (10:1), which can cause a bit of build up on the plugs and cause them to misfire. My leaner cruising AFR's eventually burn this build up away, making the misfire disappear.

[DC_GTST]

Had similar problem myself while back, ended up being the stock coil's (identical situation). Thought it was a bad-batch of fuel, emptied the tank...re-fueled and still had same problem. Changed to Splitfires and not a problem since. When the engine has been running a while the coil's heat up, hair-line gaps form (that you can't see when the engine/packs are cool) - that was my problem (there are a few threads to fix this).

Alternatively can be the AFM.

[SargeRX8]

Can be an intermittently failing cas. It could be many things but its stopped. Until it comes back I don't think it would be much worry. As said above, could just be carbon build up.