Russ444

So I think I have read most of the threads on misfires and they were helpful but am hoping someone can help me pinpoint the problem a little better so I don't end up changing a lot of unnecessary parts. Here's my story (with pictures) i'll try and make it short...
About 2 months ago I noticed my '03 OZ would stutter once in a while at low RPM's (usually 2nd gear) and I just passed it off as bad shifting and my car getting older (104k on it). As time progressed it got a worse, so I re-charged my K&N air filter (SRI) as it was quite dirty. Reset the car (unplugged battery for 10min). I would have changed my plugs but had done that about a year ago so didn't think it was the problem... The problem continued and then my check engine light came on. Got my code read at autozone as P0302 which was:

Cylinder 2 misfire condition.
Probable Cause
1-Ignition system faulty.
2-Fuel system faulty- Injectors or pressure
3- Vacuum leak

Pretty much what most people say on the forums here. So I changed my plugs (changed from champion to NGK) and wires as the Autozone guy suggested. When I changed the plugs one of them was definitely in much worse shape than the other three (cylinder #2, see pics.), the wires seemed fine (pics). So after changing them, the car worked great for about 3 weeks, thought I had it fixed. Now i'm starting to notice the same problem again. Stuttering when you try to accelerate quickly at lower RPM's, if I go slowly and shift at the higher end of my gears I don't notice any stutter. And my check engine light just came on again.
So am wondering if someone can lead me to the right next step. I am going to go to autozone again to get the code checked and am wondering what parts I should consider buying. Probably the coils are next but that rarely seems to fix this problem, at least according to these forums... Am not super car tech. savy but am trying to learn... perhaps just some fuel injector cleaner?

Thanks for any help anyone can provide!

*02Lancer*

iTrader: (3)

When you installed the plug's and wires did put dielectric grease on the end's of them. Thant might help i dough the problem would be fuel or vacuum if when you changed the plugs the first time it fixed. i would try that and see if it helps. Good luck misfires are the hardest to find. And keep up posted on how it comming and when you fix it.

Russ444

No I didn't apply any dielectric grease, I saw the thread that said it helped you out. I'll give it a try, I sure hope it's as easy as that. How much grease do I apply? Just a thin coating on the wire before I plug it in?

*02Lancer*

iTrader: (3)

I pulled my coil pack out and put it on the bottom of them and at both ends of the plug wires and I was not conservative with how much I put in. If you know what a starburst jelly bean looks like about that size lol. Hope it helps those plug's you have pic's are those the new one's if so they look like they might be too cold of a plug and are getting oiled fouled. I would make sure they are the right ones.What number is on the plug i cant see the hole number?

mcgarvey

Once the plug wire or coil pack boot is carbon tracked, it's junk. It sounds like a defective coil to me. If you already replaced the plugs and wires, go ahead and replace the #4 coil, which controls the #2 cylinder's spark. Also like they said, dont skimp on the dielectric grease (3m silicone paste is the same thing and much cheaper). It's most likely not a vacuum leak-- the only place a vacuum leak could cause a single cylinder to miss would be a leak at the intake manifold gasket into only one port (unlikely!). The injectors are trouble free on this car and problems with them typically cause a lean code, not a miss. My guess is it's the coil.

Here's a simple way to test it (assuming you've already replaced those nasty carbon tracked wires): Switch the coils, and see if the misfire moves to a different cylinder. (ie, a p0305 instead of p0302 like you had).

Oh and one more thing-- what plugs are you running? NGK BKR5E11s are the way to go and are less than $2 a piece. Waste spark systems like ours often have problems with platinum plugs and all the other BS that's out there.

Russ444

Ok, thanks for the great input. To start off, the pictures of the wires/plugs I posted were the old ones, factory wires (never changed before) and some champion plugs that I replaced about a year ago. 2 weeks ago I installed NGK plugs (BKR5EGP, platinum) as that seemed to be what most people recommended here on the forums. Sounds like maybe I should have gone with the NGK copper plugs? I suppose that's pretty cheap to change if you really think it might be a problem.

So, I went to autozone yesterday and got my code read (P0302, misfire on #2 again) which I was relieved to see since we can focus on one thing here. I got some dielectric grease and applied it to both ends of the wires and the connecting part of the plugs. Also put some on the coil connectors. Sounds like I could have been a little more liberal with it but I added a decent coating.
Now, I'm a little confused as to the cylinder/coil pack order. I'm not sure this is right but do the cylinders go from left to right when you are standing in front of the car looking at the engine, 1,2,3,4? Putting coil packs on #2 and #4, with cylinder 3 plugged into coil 2 and cylinder 1 plugged into coil 4? If this is the case then the fouled up spark plug that I posted a picture of was on #3, which made me wonder why I would have a misfire on #2... that's a little confusing hope it makes sense or that someone can straighten me out.
Anyways as I was adding the dielectric grease on my version of coil pack #2 I noticed that the boot had what looked like an arc marking on it (see pic). Is that bad enough damage to cause misfires?
Either way, after I greased it and put it all back together I took it for a test drive and adding the dielectric grease definitely made a difference. Although I made a really poor shift into 2nd purposefully and there was a slight stutter but much less than I was used too. Maybe just bad shift stutter, I'll have to drive it a little more to be sure.

*02Lancer*

iTrader: (3)

eww yah that boot would allow the spark to jump and not fire the plug. dielectric grease does not conduct eclectric which is why it helped you i would try and get a new one and that should fix it. you can try putting more dielectric grease on that one if you feel that there is not enough and see if that makes it even less noticable. That could cause your plugs to get messed up being that they and not firing.

Russ444

Ya, I thought that boot looked a little rough. So is there a way to just replace the boot on the coil instead of the whole thing. When I had it out it didn't seem like it just pulled apart or anything but then again I didn't pull it that hard. I did find what looked like just a replacement boot at Autozone but there wasn't much of a description.

*02Lancer*

iTrader: (3)

That i honestly do not know i have never replaced that on my car. Im home till monday when i get to school i can look it up on alldata for you.

Russ444

So my curiosity got the best of me and I removed the coil/boot and looked at it closely. After applying some gentle pressure the boot popped off no problem. It's nice to be able to replace a $20 part instead of a $90 part. I havn't replaced the boot yet as after applying the dielectric grease my car runs so much better. But I am sure that must be the culprit of the misfires, the grease is just helping it out a lot at the moment. I will replace it soon and if I do and the problem comes back i'll post something. Otherwise I think the problem is solved and I wanted to thank all who helped me solve my problem, especially 02Lancer! Thanks!!!

*02Lancer*

iTrader: (3)

Hey thank's hope you dont have to deal with this problem again but if you ever do just message me and i will see if i can help.

my-lancer

iTrader: (10)

I had the same problem awhile ago and went to autozone and got the same code. I changed coil packs, wires and plugs and it worked for awhile. started up again aliitle later and finally checked the connector from cylinder 2 and thats what it was. loose connector was the problem. Check that if all else fails. hope your car's running good.

stupidhonda

Thank you for this post. I read it searching for a fix for my car. My 2002 Hnda Accrd V6 had a very long crank time to start, multiple misfire codes, and finally the CEL light started flashing while I drove it the last time. I parked it to save any damage to the catalytic converter. The last time I took it to the dealer they said the plugs were good. Their diagnosis was a new ECM ($900) and they wanted to drop the gas tank to "have a look" inside ($1600).

After reading this post, I pulled the coils and found some carbon tracking on the coil boots. So, I packed dielectric grease in the boots and also replaced the plugs as they were bad IMO. I cleared the codes and it fired up a little slow but smoothed right out and has fired up perfectly since then.

Thanks again for this solution!!!