This started to happen after I spilled on the engine, appx 2oz, during DIY oil change.

It only happens at the very first start up of the day even in this weather, 70-80F.

If I start her up while I step on the gas pedal and keep RPM at 1.5k -2k for 10-20 sec then it's ok. Even if I don't start with gas pedal stepped on it lasts only abt 30 sec then everything runs fine. OBD shows it's misfire in cylinder 1,2,3,4. Can oil spillage cause this misfire? It's never happened before this oil mass. Apparently oil did not smear into any of cylinders. One of the tech says it's coils that causing this problem/misfire.

my question is; can oil spillage cause misfire? How? Should I just get coils replaced?

 

Hey BBC,

If you spilled oil onto the top of the valve cover it should not have gotten into the ignition coils themselves. I have seen some powerful degreasers sprayed on the engine and never cause an issue with the Ignition coils. Verify no oil is in the connectors them selves, though. If there is, then get some electrical contact and spray the connections lightly, and wipe the excess away. DO NOT spray alot, just a quick blast and then wipe clean with rag. Both sides of the wiring connection will benefit if they are full of oil.

Just to note, I have seen that kind of RPM fluctuation caused by slackened timing chains/tensioners(valve timing out of spec), along with Valvetronic motor faults. Seeing as it will go away and your not dealing with sub-zero temps, in my opinion it cannot be valvetronic issues. Both of these faults can cause multiple cylinder missfires as your fault code check states.

Has the timing chain or tensioner been replaced before? Has your car been run low on oil recently? Does it make an ugly rattle sound on cold start-up?

These questions can lead to a better understanding of what your dealing with.

Happy motoring,
dthtrp