so the check engine light in my girlfriend's car came on the other day and when autozone scanned it for me they said it was a cylinder misfire (cylinder 4 to be exact).

she has a coil-on-plug setup in her engine. it's a 2003 4cyl with 33k miles on it. i plan on pulling the plugs and coilpack out this weekend to take a look at it, but the way i look at it, the plugs should still be good unless the plugwell seal is leaking oil by. the guy at autozone did mention to me that they stock the coilpacks in-store. now from my experience they don't usually keep things in the store unless they're a popular item. usually something comes from the warehouse that is rarely purchased.

by this rationale it seems to me like it might be common to have a dead coilpack. does anyone have any experience on this before i spend $110 on a coilpack that might not solve my problem? does anyone have a testing procedure i can use on the coilpack in the car to see if it's good? i'm quite inclined electrically and mechanically so if anyone out there has an idea i will definitely try it.

Thanks in advance!

Bob (SSTS)

 

dont mitsus have a 3yr 36k mile warranty?

 

Before you do anything take it to the dealer. Could be a dead coil pack. I had a bad coil pack on the TL and it was misfire hell. Changed the coil pack and all was good. Check all the plugs and post what color they look like.

 

i'll have to check, but as far as i know her warranty would be up by now. she bought it used this year and as far as i know it is just past the 3 year age mark. i will double check on that today if i can. i'm not sure where i can find the manufacturing date on the vehicle. i remember on my taurus the date was stenciled on the quarter panel in the trunk. but then of course you have to make an appointment and she doesn't have another car to get to work anyway so that's a day of lost wages. i would rather fix it myself at that rate, but i'll double check to see what they can do. thanks for the idea though.

SSTS

 

Same thing happend to my CL-S.

 

well i called mitsubishi with the VIN # and they said the in-service date of the vehicle is recorded as 11/08/2002, so she has 3k miles or 3 months left on the warranty.

my only complaint is that if she takes it in she loses a day of work because she doesn't have another ride, so in the end paying $110 for a coil pack would be cheaper than losing a day's wages. plus the fact that she would have to wait 2 weeks for an appointment and the local mitsu dealer has the worst reputation in the area so i don't know if i would trust them to not screw us. decisions, decisions.

she says the CEL hasn't come back on since they reset it last night, but if anyone pops out with a procedure for testing coil packs i'm still interested for my own personal amusement.

thanks.

SSTS

 

Driving two weeks with a misfire =

Drop it off tomorrow (since it's the weekend). Make them give her a loaner for two weeks under warranty because it could seriously fuck up the engine if she drives it for that long.

 

unfortunately the local dealer won't give her a loaner since she didn't buy the car from them (i called them yesterday), but i agree that it's not good to keep driving as is. she says she can feel it stumbling even though the CEL light hasn't come back on. my buddy explained to me that OBDII might not necessarily bring up the CEL again for the condition.

my mechanic friend is going to pull some strings and try and get me the coilpack for free through someone he knows. so long as he comes through today i'll just fix it myself.

SSTS

 

so i swapped the coil pack out with a new one (courtesy of my hook-up from the parts store) and voila the problem is gone. i kept the old one so i could test it for my own amusement. otherwise the plugs were fine ( i was too lazy to take photos). they showed normal wear and tear for 33k miles.

thanks for all the help guys!

Bob (SSTS)