Jayc87

Had a small hesitation on car around 2 to 3k on part throttle once throttle moves a bit theirs no jerkiness/ hesitation. Pulls into vtec with no hesitation fine.. just the low rpm area..
checked plugs their fine and gapped right.. only thing i havent replaced is the coil packs..

not had a coil car before took coils off to have a look, there is a slight rattle on all 4 coils when move them in your hand and spring is to me coming uncoiled..

Nick Graves

Any OBD2 codes showing?

Might as well replace them if in doubt - it's not VAG shite, where you need to replace them like oil filters.

Jayc87

No codes since re did the cam sensor wiring on inlet side. Previous to that did have p1399 but that was with the p1762 for cam sensor.. saw the split wire sorted that and no codes.. but just small hesitation jerkiness at low rpm

Nottm_S2

I had high rpm stutter on a boosted car due to coils.. that was a 99. My 01 is on the originals

​​​​​​Rockauto are cheap but a bit slow, especially at the mo.. think the UK places are getting cheaper, tegiwa etc

O2 sensors good?

Jayc87

02 has thrown no error codes.. injectors were rebuilt and cleaned etc.. im stock apart from a k and n engine wise..
from say 3.2 ish revs their is no issues smooth as butter.. and its only part to full throttle at low rpm the issue arises.

Daytona-Dave

the spring isn't becoming uncoiled it's meant to be like that so it contacts the top of the plug under pressure when it's tightened down, you won't tell anything just by looking at it unless it's cracked or burned, to test them you would have to get them scoped or swap with a known good one but they do seem to create problems later in life hence why most folk change them,,Rockautos being your best bet

Jayc87

Thanks for clearing that up. I get a set and see if that clears it up.. think a freind has some spare from his f20 kit car..

Nottm_S2

They are silly money in the UK, hence the advice.

I looked and Teg are selling Denso at £77 each where i paid half that imported iirc

Jayc87

Only other culprit could be the 02 primary.. maybe as it sat over winter in the manifold whilst i serviced rest of engine..
could be slow to react..
Again id suspect it like coils is best to swap for a known working one or buy new oem.. again expensive

Daytona-Dave

Your O2 sensor operation and reaction time can also be checked on a scope, but if it's slow to react from a winter layup an Italian tune up would soon put that right, an O2 sensor would have to be pretty far gone to cause a misfire to the point it would put the management light on, that would more likely be map or the little o ring it sits on, air leak check all your vac pipes are on or sealed, fuel a bit off from standing or the coils