1.4 tu3jp (KFW) intermittent misfire

[SketchYDG]

Hey all

Got an intermittent misfire on my engine (details of engine in title). I've changed the coil pack and spark plugs. The misfire went away for 2-3 days, then came back again. Misfire now occurs on start but then goes away. Then misfires at random throughout Rev range and all gears. No consistency to when it happens.

Any ideas of how I can solve this?

Also noticed that the power drops around 5000rpm in 2nd then comes back again, could this be related?

Many thanks in advance for any help.

[Will97]

Have you thought about doing a compression test etc when cold? The misfire could be due to the start of a head gasket leak where water is seeping into one or two of the cylinders as the engine cools down and contracts, especially if it happens on startup then goes away as the engine warms up ... The engine expands as it warms up and therefore seals the leak until it contracts again.