Hi all,
I've put this in the E85 section but it's a generic N52 engine question so hopefully other see it.
I keep getting a very slight stutter occasionally as if one cylinder misfires just once, usually under light acceleration at modest revs. No errors logged, of course. If I can find an hour later or this weekend, I need to start by looking at coils and plugs. Two questions:
1) Anyone know of any tell tale signs they've seen in a similar circumstance?
2) Is there anything else in the N52 that might cause this? Sign the O2 sensors are on the way out? Sticky VANOS solenoid (I replaced one a couple of years ago that was causing proper poor running complete with errors and cleaned the other)? Something convoluted involving the valvetronic?
I actually feel somewhat stupid asking this - I'm an engineer of many colours and, though I feel nothing more than a tinkerer, I have barely ever paid a garage to do anything car related in 30 years - but I keep worrying it's something more complicated than a loose plug and I can't think of a definite way of eliminating the coils (unless the secondary of one has actually gone open circuit) and loathe the ideal of replacing them willy nilly.
I've put this in the E85 section but it's a generic N52 engine question so hopefully other see it.
I keep getting a very slight stutter occasionally as if one cylinder misfires just once, usually under light acceleration at modest revs. No errors logged, of course. If I can find an hour later or this weekend, I need to start by looking at coils and plugs. Two questions:
1) Anyone know of any tell tale signs they've seen in a similar circumstance?
2) Is there anything else in the N52 that might cause this? Sign the O2 sensors are on the way out? Sticky VANOS solenoid (I replaced one a couple of years ago that was causing proper poor running complete with errors and cleaned the other)? Something convoluted involving the valvetronic?
I actually feel somewhat stupid asking this - I'm an engineer of many colours and, though I feel nothing more than a tinkerer, I have barely ever paid a garage to do anything car related in 30 years - but I keep worrying it's something more complicated than a loose plug and I can't think of a definite way of eliminating the coils (unless the secondary of one has actually gone open circuit) and loathe the ideal of replacing them willy nilly.
