spark plug goes bad every1000 miles!

[karlsranger]

My neighbor has a 98 4.0 liter Ranger 4X4 with 136000 miles.It started misfiring when cold.He took it to a local mechanic. Three times. Maybe $1000 worth! Had a #4 sparkplug code. Changed the plugs plug wires coil packs and intake manifold gaskets. The problem kept coming back! A bad miss when cold and occassionally noticeable at warmed up highway speeds. I offered to help. Cleaned the idle air mechanism and replaced #4 plug. The plug had a current track at the end of the insulaltor. Looked like the current was going to the head and not jumping the gap! Truck worked well for two weeks then same thing! I changed the #4 plug and the problem went away. No current track this time. What's going on here? ( Sorry about not having a working comma)

 

[BrooklynBay]

Welcome to this forum! What brand are you using for the spark plugs? What do the plugs look like when you take them out? Are they full of oil, have a powder coating, or look rusted?

 

[ExploringNC]

Post a good closeup pic of the bad plug. What brand and part number plugs is he using?

 

[BrooklynBay]

He sent me an email about this problem a few day ago, and said that he has Autolite AP103 plugs.

 

[manaen]

sounds like that cylinder could be burning oil which is fouling the plugs which will cause the "current track" as he calls it to short out the plug. I've seen it in motorcycles all the time. unfortunately if it is fouling the plug then it must be the rings since the valve seal will only leak during high vacuum and not foul the plug.

If that diagnoses is correct the plug will not be burning clean and will have dark residue burnt to the insulator.

You can try a hotter running plug, or one of the plugs that claims to burn through oil etc..

Back in the day when I raced motorcycles on a tight budget I used to use a propane torch to heat up the insulators and burn off the carbon buildup, the plugs would then work again for a race or two.

 

[jah81592]

Is the plug oil fouled, fuel fouled, electrode completely gone?? Pics would be nice.-j

 

[manaen]

I so rarely get to use this

:ttiwwp:

 

[ronaldk]

had the same problem could not figure it out untill the engine blew cthere was a small crack in the intake. pressure test it and see i had no luck with anything like i said i put a whole new engine in thats how i fixed mine because it blew up

 

[daviehill80]

i have been having my #6 plug #$&@ing up on me i have had to change it twice both times the electrode has been broke off no oil or anything
so whats up can anyone help

 

[manaen]

i have been having my #6 plug #$&@ing up on me i have had to change it twice both times the electrode has been broke off no oil or anything
so whats up can anyone help

Broke off? or burned off?

advanced timing or detonation can burn the electrodes off. Is this an ohv motor?

post a picture of your plug that will help greatly.

 

[Opera House]

I had that problem with my 97. Had it because I sold it to a friend and now he has it. The problem is likely coolant leaking at intake manifold gasket. You won't see it on the plug. I couldn't see it iven with a microscope. I would get 1-5K on a plug. At a $1.37 a plug it was a cheap solution for low use vehicle. I could have fixed it, but auction Explorers are cheap and it is just easier to get another one.

 

[daviehill80]

i would say when i have changed it while inspecting it i notice it is cracked and it braks off i will work on getting some pix, also i have had many different veihcles and i got my explorer from my mother who bought it new in 99 and over the course of its life every freeze plug has rusted out and had too be replaced

 

[manaen]

Here's an off the wall possibility....
almost sounds like you have an electrolysis problem. I've never heard this happening with a motor in a car but in theory it can happen anywhere there is DC current, or the potential to make DC current (like in salt water). I would go over all your ground lines and also take a volt meter an make sure you have no current leaching anywhere. If you have a multimeter take a current reading on the battery when everything is off to see how much power drain is there. Do you have any other weird, seemingly unrelated electrical problems?

 

[daviehill80]

when im at a stop light or drive thur idleing in gear where there is a load on thw veihcle there is a miss that shakes the whole truck then if u put it in neutral or park it clears up perfectly

already done
new plugs new wires
new battery

 

[$$MakingMoney$$]

?

when this happens does it mess with the idle of a vehicle?

 

[kihei777]

Hello all. I've also replaced my #4 spark plug 2x in less than a year due to a P0304 code. It clears out the code. But I'm curious as to what is causing the code. Closer inspection of the spark plug reveals brown residue on the threads (see pics). I actually have to clean it off with a steel brush just to get it out...not sure if its oil, dirt, coolant, etc. The actual spark plug looks good except for the threads. Any clues? Please help.

 

[The Captain]

My explorer does the same thing which its a 96 5.0. But I have 3 spark plugs doing this. Mine looked and smelt like fuel and also some oil was on them. Looks like I need to clean them again because how you know something isn't right is when the your car gets kinda chuggy on acceration and load. Also gas mileledge gets ****ty.

I used to use those E3 plugs and they worked great and cleared all the carbon oil and fuel. However they only lasted like 7 months and then each one started to foul and my explorer barely ran.

Motorcrafts Plats. work great but you might have to clean them like me.

 

[Dono]

Hello all. I've also replaced my #4 spark plug 2x in less than a year due to a P0304 code. It clears out the code. But I'm curious as to what is causing the code. Closer inspection of the spark plug reveals brown residue on the threads (see pics). I actually have to clean it off with a steel brush just to get it out...not sure if its oil, dirt, coolant, etc. The actual spark plug looks good except for the threads. Any clues? Please help.[/IMG]

Have you noticed your coolant resevoir keeps slowly going empty? I thought my issue was lower intake leak, but it was cracked head. It sucks coolant, and the spark plugs insuator cracks. Just a hair line. Repl. plug, and your good to go for a while.

It got to the point where I knew if I did a few WideOpenThrottles, Id have to replace my plugon #3. Then, same thing started happening on #4. There goes the second head. Replaced heads, and no coolant loss or spark plug replacement any more.