low compression - #3 cylinder
#1
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low compression - #3 cylinder
My CEL light came on with a misfire code (#3 cylinder). I assumed it was a plug, coil, or fuel injector since the engine seemed to still be running strong. I replaced the coil and plug and the CEL code was still there. So, today, I decided to run a compression test and this is what I got...
#1,2,4 - all around 238
#3 - 120
I am assuming I have a bent valve. Does anyone have any advice? (I am out of warr.) I am positive I have never mis-shifted.
Thanks
#1,2,4 - all around 238
#3 - 120
I am assuming I have a bent valve. Does anyone have any advice? (I am out of warr.) I am positive I have never mis-shifted.
Thanks
#5
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did you overrev recently. if so that would be a bent valve. if you haven't it may be a head gasket failure. either way you'll have to take the head off to find out
#6
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I would do a Leakdown test before teardown. It will narrow down what the problem is. Compression checks are a good quick check, but a leakdown provides more information, such as what valve may be leaking, scored cylinder wall or a blown headgasket.
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#9
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If you haven't mis-shifted, then it's probably not a bent valve. More likely suspects are a burnt valve or head gasket leak.
As has been said, it needs to be fixed, so you might as well let them remove the head. Then the cause will become apparent.
Denis
As has been said, it needs to be fixed, so you might as well let them remove the head. Then the cause will become apparent.
Denis
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I've got the same problem except on cylinder #1. Had a dealer in KY fix it for $1600 (bent valve, cracked valve guides - i think). Drove back to cali ~3K miles, and it's back again. Same compression numbers as before, first cylinder sucking. Talked to honda, and they said they'd look at it, but if it's a bent valve again, they won't help me, and i have to pay tear down fees. I've never overrevved her. Don't understand what the problem may be. Any input you guys have would be great, I'll post some more details once I find the receipt from KY. Oh ya, when we pulled the head in KY, there was a small ding on the piston head, so the valve def. made contact. Thanx.