Hi all, again!
Patient is: 1.4TFSI CAXC - Liqui Moly TopTec 4200 5W30 - ~206.000KM on the clock - Timing replaced at ~178.000KM
Will most likely take it to a proper garage at the end of the day, but i wanted to check if anyone has different opinion / had similar case.
Cylinder 2 has started misfiring on cold starts - as in the engine has sat overnight, the ambient temperature does not matter, it can be close to 0 or 30 degrees Celsius, and its not consistent, sometimes it happens and sometimes it does not.
That issue has already begun a while back at ~190.000KM, so i had it walnut blasted which seemingly fixed the issue up until now.
Did a simple head gasket test with a cheap kit for expansion tank, all good there.
Did a compression test on all cylinders (spark plugs looked fine and the same across all 4 cylinders). #2 sits at crisp 15PSI(~1bar) lower than rest, which technically is still within spec.
But clearly something is causing issues there.
I do not have excessive oil consumption, since my last oil change ~6.500km ago i have lost about 250ml of oil which might have leaked out of the oil filter because i noticed some oil there(cleaned the area and re-torqued filter).
My suspects are:
- Piston rings
- Valves/Seals
- Lifters
I doubt and hope its not the piston rings. I suspect Valves themselves might not seal perfectly anymore.
As for lifters suspicion, cold starts sometimes carry with themselves a nasty ticking/taping sound, different from injectors,
That sound gets more intense with higher RPMs but disappears when oil gets up to Temperature ~20 to 25 degrees.
At first i was worried about piston slap, but i reckon i would feel much more vibrations and hear a deeper more metallic sound. I doubt it is the chain as the garage did the work less than 30.000KM ago and put in the revised kit, it could also be the tensioner starving of oil until its viscous enough? but then again, i would expect the whole engine to run like bum before i bend my valves, while its only cylinder 2 misfiring every now and then.
Any theories & ideas are welcome.
Patient is: 1.4TFSI CAXC - Liqui Moly TopTec 4200 5W30 - ~206.000KM on the clock - Timing replaced at ~178.000KM
Will most likely take it to a proper garage at the end of the day, but i wanted to check if anyone has different opinion / had similar case.
Cylinder 2 has started misfiring on cold starts - as in the engine has sat overnight, the ambient temperature does not matter, it can be close to 0 or 30 degrees Celsius, and its not consistent, sometimes it happens and sometimes it does not.
That issue has already begun a while back at ~190.000KM, so i had it walnut blasted which seemingly fixed the issue up until now.
Did a simple head gasket test with a cheap kit for expansion tank, all good there.
Did a compression test on all cylinders (spark plugs looked fine and the same across all 4 cylinders). #2 sits at crisp 15PSI(~1bar) lower than rest, which technically is still within spec.
But clearly something is causing issues there.
I do not have excessive oil consumption, since my last oil change ~6.500km ago i have lost about 250ml of oil which might have leaked out of the oil filter because i noticed some oil there(cleaned the area and re-torqued filter).
My suspects are:
- Piston rings
- Valves/Seals
- Lifters
I doubt and hope its not the piston rings. I suspect Valves themselves might not seal perfectly anymore.
As for lifters suspicion, cold starts sometimes carry with themselves a nasty ticking/taping sound, different from injectors,
That sound gets more intense with higher RPMs but disappears when oil gets up to Temperature ~20 to 25 degrees.
At first i was worried about piston slap, but i reckon i would feel much more vibrations and hear a deeper more metallic sound. I doubt it is the chain as the garage did the work less than 30.000KM ago and put in the revised kit, it could also be the tensioner starving of oil until its viscous enough? but then again, i would expect the whole engine to run like bum before i bend my valves, while its only cylinder 2 misfiring every now and then.
Any theories & ideas are welcome.