The engine was misfiring twice this week and both times the cause was a spark plug on cylinder 5 that kept getting the electrode smashed. The first time I changed it and the engine seemed normal. The second time i changed it the misfire went away, there are no codes so the engine SEEMS normal again, but now there is a ticking sound on that side of the engine (driver side, possibly cylinder 5). The sound reminds me of a bad lifter, but I am wondering if it is a badly bent valve? Could a damaged valve been the cause of the damage to the plugs?
- I was only using the motorcraft plugs recommended for that engine
- Both times the misfire (damage to the plug) happened after a powerful boost (don't know PSI)
you would know if the supercharger blew...
ticking...if it just started with the plug getting damaged, could it be a part of the plug? There's definitely something going on and I wouldn't drive that til you check it out. Or if you have to, stay realy light on it.
Damaging spark plugs twice definitely means something up.
is that spark plug the same as all your other ones? if its the same one you bought make sure its the actual same one maybe a handling error has put different plugs into your plugs packaging. Two things could occur from that, the plug physically being hit or maybe its burning too hot/cold.
Boost or spray you need to go down a heat range. Plugs break, it happens...when I was trying to find my plug gap I was shitcanning Autolite plugs every 1,000 miles or so. That gets expensive at $150 a set, but I learned that Autolite (Motorcraft also) plugs are garbage from that experience. Stop driving it, get it borescoped to see if there is still a chunk of something in your cylinder...if it gets in a valve, or stuck between your cylinder wall and ring land, you're fucked.
Yeah I hear you, but those plugs don't look like they detonated. They look like something hit them. I took it down a heat range from what it was before. The plugs that were pulled out of the engine were at .05 and I took them down to .04. History: at .05 the S/C was fine, but I needed to change the plugs because of MMT fouling. Some a-hole used additives. That was when I regapped the new ones to .04 and ran like that for about a month. Eventually the CATS went from A/F I guess (no gauges yet). I replaced them with highflows, changed all 4 02s and changed the coil pack because cylinder 5 was not firing. 1 week later I blew the first plug - the ceramic around it was broken and the electrodes were touching (no Gap). I replaced it with another plug and that one blew 4 days later when I gunned it off the line (I was gunning it the entire time since the first plug blowout and no problems). When the second plug blew the tip was now past the electrode. Something is definitely hitting it. I am having it scoped right now and hopefully I wont have to do a head job (pause).
Right, I never said it was detonation. Whatever is hitting your spark plug, like a chunk of ceramic from another plug, could still be in your cylinder...whacking your valves and scoring your cylinder walls, and punching your spark plugs. I read what you said. Did they find anything when it was scoped?
You can take the serp belt off and listen to the motor. Not gonna hurt a thing as long as you dont let it get hot.
Post pics of the plugs. The first plug the was damaged, did you find all of the peices? I'm gonna bet that you have a peice of that spark plug inside the motor. You def dont want that peice droping in the combustion chamber and eating the #5 piston up, lol. Be a good idea to pull the head before any damage is done.
btw...once you fix this issue you should switch to the ngk-tr6($2.00 plug) and gap it at .030.
Edit...1st of you were running to much gap and were running the wrong heat range plug. Probablly heated it up after numerous runs and it had enough. Do as I suggested above to avoid any damage to other cyl.
The ceramic piece is still in there and it already starte eating up the piston. you can see metal shavings in the oil. The heads have to come off and get machined ($2800!). Not doing that right now, just finished dropping $1500 worth of exhaust work + $300 for ignition work. That will have to wait until the spring. I'm just going to have them flush the engine and we'll see what happens from there. What' the worse that can happen? At $2800 to machine only one side of the engine, might as well drop another motor in and reuse the components from this one for a few hundred more. I will switch out the plugs once I get the car back. Thanks
PS This SUCKS! ESPECIALLY SINCE I'M NOT EVEN GETTING ANY PERFORMANCE MODS OUT OF IT!