Mechanics

WHAT WOUKD CAUSE AN INTERMITIT MISFIRE IN A CYLENDER

2003 Mitsubishi Eclipse • 126,000 miles

When the engine light comes on it reads cylender 2 misfire. I replaced the map sensor, throttle position sensor, and the fuel injectors. But at an idle the car runs good and and if I slowly apply the gas but if I hit the gas hard or fast it will mosfire and the engine light will come on. There is no vcume leaks or intake leakd. There are new plugs and wires. I switch the coils around and still cylender 2. Now last night I started to take the engine wire harness out and checked the connectioms. Put it all back together and she ran great. I went out this morning and back to the misfire now I am lost. Any one have any ideas?
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Read3056
October 8, 2012.




Check the spark plug wire at the cylinder. Wiggle the injector wire harness connector to see if there are any changes. Seems like something is loose somewhere.

KHLow2008
Oct 8, 2012.
Yea all the connectors are tight and they are all plugged in. I'm not sure why she came out of it for a little while last night but its still acting up and when it kicks the engine light on it runs 10 times worse

Tiny
Read3056
Oct 8, 2012.
In neutral or any gear I can slowly accelerate to any rom without issue but if I accurate kinda hard it will sputter in neutral and all the gears

Tiny
Read3056
Oct 8, 2012.
You need to retrieve the trouble codes for the MIL indicating. Let me know the EXACT code and we shall see what needs to be done.

KHLow2008
Oct 8, 2012.
I believe the code was p302 not sure but I looked it up and said it was misfire in cylinder 2 but I erased the code and runs better but if it gets into a bad sputter it will set the code and run 10 times worse. If I am easy on the throttle the engine light won't come on

Tiny
Read3056
Oct 8, 2012.
Yup, a misfire in cylinder # 2. If the spark plug wires are not OEM, I would repeat my suggestion of having it checked.

KHLow2008
Oct 8, 2012.
I have somewhat of the same issue - had several fault codes that called out #2 cylinder misfire -after clearing codes no light lately - but quick acceleration causes stumbling. Working through troubleshooting but haven't found any smoking guns. Currently troubleshooting injector system. Very weird symptoms.
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Tiny
Rhondalmorgan
Oct 14, 2012.
What were the codes retrieved?

KHLow2008
Oct 14, 2012.
PO302. Weird thing is haven't had a code light for a while now but symptoms are getting worse. Plugs are golden tan. Electrical is in excellent condition.

Tiny
Gregmorgan1
Oct 14, 2012.
My problem ended up being the boot coming off the coil on the number 2 cylinder. It threw me off cause I swapped the coils with the boots attached and it was still reading cylinder 2 misfire, but I don't think the computer cycled through to put out the new code. But I got a wire and boot set from advanced and she came out of it. But I've been driving around and my light still hasn't gone out yet, gonna have to have it checked tomorrow to see if it just didn't clear yet.

Tiny
Read3056
Oct 14, 2012.

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