oiled coils replaced, now getting misfire when warm
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oiled coils replaced, now getting misfire when warm
Our 2001 EX sedan with manual began suffering catastrophic misfiring about six months ago. All four of the spark plug tubes had oil pooled in them, and I replaced the coils with these aftermarket coils from Amazon:
I also replaced the spark plugs with these:
We replaced the oil tube seals on the valve cover and the valve cover gasket and are running leak-free.
After installation, the car starts and runs normally but after warming up begins to idle more roughly. I also get occasional power drops under hard acceleration, something that never happened before with the old coils. The car ran perfectly until I believe one or two of the original coils failed from oil infiltrating from the leaking into the tubes. (When I first went in, three of four cylinder tubes were soaked in oil, and the fourth had minor leakage.)
The reviews on the aftermarket coils are majority positive, but a few people had problems with misfiring.
OEM coils ( 30520-PVJ-A01 ) are $57.25 each (or $229 for a set).
The onset of the misfire was coincident with the oil on the old coils. The new coils and plugs work perfectly until the engine is warmed up, but then begin to misfire at idle, causing roughness and varying rpms. I also got one set of misfire codes on OBD on all four cylinders plus the general misfire code, but those haven't come back, though the erratic idle when warm continues. I am doubtful that EGR or other failures coincide with this. THe catalytic converter consistently comes up with p0420 code ("efficiency below threshold") since a dealer ran some kind of cleaner though several years ago (thanks!), so I suspect the O2 sensor is OK.
Any experience here on aftermarket ignition coils on 7th gen EX 1.7 engines? Should I spring for the OEM coils?
Those NGK plugs are marked as compatible (heat range, OEM part nunber PZFR6F-11 vs ZFR6FGP, the OEM are $12 each ), no issues on Amazon reviews including a couple of CIvics, but could that be a cause?
I also replaced the spark plugs with these:
We replaced the oil tube seals on the valve cover and the valve cover gasket and are running leak-free.
After installation, the car starts and runs normally but after warming up begins to idle more roughly. I also get occasional power drops under hard acceleration, something that never happened before with the old coils. The car ran perfectly until I believe one or two of the original coils failed from oil infiltrating from the leaking into the tubes. (When I first went in, three of four cylinder tubes were soaked in oil, and the fourth had minor leakage.)
The reviews on the aftermarket coils are majority positive, but a few people had problems with misfiring.
OEM coils ( 30520-PVJ-A01 ) are $57.25 each (or $229 for a set).
The onset of the misfire was coincident with the oil on the old coils. The new coils and plugs work perfectly until the engine is warmed up, but then begin to misfire at idle, causing roughness and varying rpms. I also got one set of misfire codes on OBD on all four cylinders plus the general misfire code, but those haven't come back, though the erratic idle when warm continues. I am doubtful that EGR or other failures coincide with this. THe catalytic converter consistently comes up with p0420 code ("efficiency below threshold") since a dealer ran some kind of cleaner though several years ago (thanks!), so I suspect the O2 sensor is OK.
Any experience here on aftermarket ignition coils on 7th gen EX 1.7 engines? Should I spring for the OEM coils?
Those NGK plugs are marked as compatible (heat range, OEM part nunber PZFR6F-11 vs ZFR6FGP, the OEM are $12 each ), no issues on Amazon reviews including a couple of CIvics, but could that be a cause?
If you think a good mechanic is expensive, try hiring a bad one
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Re: oiled coils replaced, now getting misfire when warm
Driving with misfires can ruin the catalytic converter in a hurry,
it could clog up the cat, or the guts of the cat could break apart and the loose chunks could clog up the exhaust at random times
it could clog up the cat, or the guts of the cat could break apart and the loose chunks could clog up the exhaust at random times
Dr Krieger of Modification
Joined: Jul 2010
Posts: 3,407
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From: canada
Rep Power: 228 Re: oiled coils replaced, now getting misfire when warm
Check to make sure the coil clips are clicked in all the way... freaked out for a few hours once when I left one half clipped, lol.
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