Well I started gettin a CEL a few days ago, and the old girl started workin a little bad....turned out to be P0308, misfire #8, so first thing I did was reroute the #8 wire over the valvecover as it should be. That didn't seem to make a difference, so I figured it was just time for plugs wires cap n rotor. I pulled the #8 plug tonight and found the cause of my misfire:

The insulator is broken and fell down by the electrode, and theres a bunch of gunk on it

Here's #6 and #8, they all pretty much look like #6 except for 8 of course...



Well since I need plugs etc anyway I decided to pull em all.... I'll have to take the wife's blazer (ugh ) to pick up some parts tomorrow... These are all in order of how they would be sitting in the motor.... yeah I broke #7 off, RIGHT after tellin the wife that she'd probably break it, cause she wanted to try pullin out a sparkplug...


So does this look like I have a problem with #8? Or just a failed plug? And how do the rest look? I dunno how long they've been in there, I don't think I've changed em since I've had it, but now that I'm thinkin about it I dunno..... And what do you guys recommend for plugs and wires? Keep in mind I don't wanna spend a small fortune, I was planning on doing all the tune up stuff when I do the plenum fix, but that won't be til a little later....

 

Too hard to tell. I've seen gunk like that accumulate for a variety of reasons. Replace the plugs, then in a few thousand miles pull #8 again. If its dirtier then the rest, you know you have a problem on that cyl.

 

good idea, I will remember to pull that and check it again... I'm hoping that it's just gunked up from being dead for a bit.... I've had such good luck with this ol girl running wise since I've had it that I'd hate to see something internal goin down.... plenum aside of course

 

Same thing happened to me man, number 8 would get engulfed in gunk and oil. Replaced the plenum. No more miss, and my number 8 plug is nice and golden brown.

 

Champion copper tops.... Don't forget to put a lil anti seize on the new threads might save ya next time, the last guy didn't on mine and a couple were a real pain in the rear. Had to soak with PB and all that.

 

If you've got the cash and want to put top quality wires on it that will last for years and years, go with Magnecor. www.magnecor.com

If you can't afford those, I recommend Taylor wires and, route them to the TSB.

Plugs, hands down- go with NGK V- powers.

Now as far as the No 8 Plug is concerned (well, all your plugs actually LOL) those are beyond anything I've ever seen. Those are in bad shape, rust and all.

Here's what most likely happened, No 8 either detonated or, it was already worn due to high mileage and just crapped out to the point where, the electrode was burned through thus severing it.

Cleaning the debris off with a brush, check the electrode and look for signs of it getting whacked, smashed, bent over to one side, rolled over etc. My guess is that you won't find that and it's just old age.

No 8 CYL sees the most heat as it's near the back and, if the converter is partially restricted, the heat backs up the exhaust into the two rear chambers primarily. This causes the two rear plugs to fail faster than the remaining plugs.

IF you don't see any evidence of mechanical interference at the plug level, place a new set of NGK V-powers in and torque them per spec to seat the compression washer.

Run it for a while, note any mechanical noise that may be emanating from that side. If not, drive it for a bit and pull the plug on CYL No 8 and inspect it for mechanical damage, bent, squashed, collapsing the gap etc. If not, it's fine thus leading us to reason that the failure was simply due to very old age plugs that had s-h-i-t the bed long ago.

However, if evidence shows mechanical interference at the No 8 plug, then you've got a problem. Again, I think it's just old age and wear and tear that led to the failure.

CM

 

Holy **** dude them things are horrible. I have never seen plugs that bad hahaha

 

Sh*t there champion plugs could be stockers, autolite plugs for sure I dont run anything else the cheap copper ones do the job just fine and are light on the wallet

 

looks like you found where all the oil from your blown plenum is going...every dodge iv done the plenum on who put some miles on without knowing about the issue...number 8 was soaked in oil...

 

If it was my money, I'd test the plenum gasket IAW with the TSB and chuck the cat just on principle. Of course, I'm often as wrong as dating outside one's species.