Car idles rough and trips codes multipule misfire on all cylinders. changed coil pack in distributor, plugs, wires, distributor cap and rotor. No change. Also Sea Foamed engine, no change. Ongoing now for about 6 months. The car does burn through oil about a quart every 500 miles although it is not blowing blue out of the tail pipe. How can I get it to run smooth again? Also the gas mileage is still great about 34-38 highway 28-32 around town
Hi. The most common cause that I have found for an " only idle misfire" is low compression. The engine needs at least 100 psi of "dry " compression to idle smoothly in most cases and if any cylinders are higher or lower by more than 20 percent of any other cylinder, you will also have an idle misfire condition felt. Should you perform a compression test, make sure to disable the igntion system completely, not just move the ignition wires out of the way as you will still have spark and the fuel injectors will still inject fuel in nearby proximity to possible ignition source. Always perform two tests, "dry" and "wet" compression. "Dry" is warm engine with spark plugs removed. "Wet" is after performing "dry" test add a few drops of light oil into cylinders and perform compression test again to see if the number rise. If they rise, you have worn piston rings or cylinder walls. If they do not rise, you likely have worn valve seats, misadjusted valves, or head gasket issues, possibly cracks in the cylinder head. If you need to know how to compression test with a tester in detail, message me back and I can help. I'm assuming you may already know due to the fact you state you replaced all the parts likely by yourself so you probably have strong technical merit.
Thank You so much, I tested out my compression and you hit the nail on the head. BAD compression on the #2 cylinder. Seems to be bad rings as I put oil in the cylinder and the reading went from 30psi to 90psi. Again thank you as the other 10 people or so that I spoke with at the auto parts stores were clueless. Now hmmmm How to fix this problem or would it be easier to just get a used engine and replace??????????????
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SOURCE: rough idle with check engine light
Usually a rough idle on a Honda is a result of the idle speed being too low. What is your RPM suring idle now. Try to increase it using the screw on the idle air control by only a quarter turn at a time. Hope this helps.
SOURCE: im getting the code p0301 cylinder 1 misfire and i
here ya go
paul
www.carburetorexchange.com
SOURCE: my 2002 honda accord check engine light has been
You did part of the tune up what about spark plug wires and spark plugs? change these also
SOURCE: 1996 Honda Accord Rough Idle Even After tune up
Perform a valve clearance inspection and adjust if necessary. Tight or sticking valves will cause a misfire or rough running concern. Note: Perform valve adjustment when the engine is stone cold. 4cyl: INT 0.26mm EXH: 0.30mm (V6 engine are hydraulic and no adjust necessary.) Also check for a sticking or stuck open EGR valve. For diagnostic purposes only: Remove the EGR valve. Place a business card over the EGR passage and bolt the EGR valve back on. This plugs the EGR ports and if the misfire goes away the EGR valve is partially stuck open and is defective.
Check for low fuel pressure. Check for low compression. Check cam timing. Check for a weak ignition coil. Also don't over look the possibility of worn or broken engine mounts which cause excessive engine movement and engine vibration. -hope this helps
Trouble Code Conditions:
Engine runtime 3 seconds, engine speed change under 1200 rpm, and the PCM detected a misfire condition present in one cylinder during the 200 (Catalyst) or 1000 revolution (Emission) test range.Note: If the misfire is severe, the MIL will flash on/off on the 1st trip!
Possible Causes:
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