Problem with rough idle and engine misfire.
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Problem with rough idle and engine misfire.
My engine isles rough when I first turn it on and actually jumps/misfires(no codes) when I try to accelerate but it usually does it when it is really hot or cold outside or after it rains a bunch, which is a problem considering I live in south Louisiana. I have cleaned all a bunch of sensors, replaced the upstream O2 sensor, replaced the gas filter and replaced the battery recently. In the last year or so I had to replace the alternator, replace the engine valve stem seals due to a leak and changed the coolant. I plan on adjusting the valve clearance because I didn't have the tool to measure it when I put the valve rocker arm back on. All of the things I have done seem to help for a little bit and then it starts running rough for short periods of time. I was wondering if anyone has a suggestion of what I could check or change to help make my car run better, thanks.
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OF top 99.5% creator (Formerly of the Puffinblunts variety)
Joined: May 2012
Posts: 3,634
Likes: 109
Rep Power: 211 Re: Problem with rough idle and engine misfire.
Perform a power balance (drop) test: by disconnecting fuel injectors one at a time and listen/look for a drop in idle in that particular cylinder. If there isn't a drop in idle rpms or drop isn't to the same extent as other "good" cylinders then that particular cylinder is having a cylinder misfire...which the ECU doesn't always recognize.
Have you checked mechanical timing? Possibly, the timing belt jumped a tooth/teeth.
Was the cylinder head removed when you replaced the valve stem seals and did the misfire issues start afterwards? Was the coolant bled correctly to get as much air out as possible..what procedure was used?
For valve adjustment all that is needed is a flat-head screwdriver, 10mm wrench, and quality set of metric feeler gauges. There is a tool that combines wrench and flat-head but, it's optional.
Here's a search that is related to moisture and misfires which may be related to your engine's issue: https://www.google.com/#q=moisture+a...ignition+coils
and this: https://www.civicforums.com/forums/3...ml#post4726721 but, test first always before replacing parts.
Have you checked mechanical timing? Possibly, the timing belt jumped a tooth/teeth.
Was the cylinder head removed when you replaced the valve stem seals and did the misfire issues start afterwards? Was the coolant bled correctly to get as much air out as possible..what procedure was used?
For valve adjustment all that is needed is a flat-head screwdriver, 10mm wrench, and quality set of metric feeler gauges. There is a tool that combines wrench and flat-head but, it's optional.
Here's a search that is related to moisture and misfires which may be related to your engine's issue: https://www.google.com/#q=moisture+a...ignition+coils
and this: https://www.civicforums.com/forums/3...ml#post4726721 but, test first always before replacing parts.
Last edited by Wankenstein; Jul 2, 2017 at 10:28 AM.
