Spark plug pic; diagnosis?

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Jan 3, 2011
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Location
Westchester County, NY
Confession time; these plugs have been in the truck since 2004, but I've only put 7,000 miles on it in 7 years. No yelling at me...

Number one is totally fouled and clogged, the rest have ash deposits etc. Can you guys tell me what's going on here, and what I need to do/should do?

I replaced them with new iridium plugs, and she seems to run fine for now(other then my other issues already posted), but what's causing the fouling, and what can I do?

As always, thanks in advance.
LC2 006.jpg
 
Well my friend. I would suggest a compression test. If #1 is considerably lower than the rest could be rings or head issues. If it sits alot do you get a puff of smoke on start up? That usually is head related. If you get smoke under normal or hard accelleration that might point to the rings. The compression and leak down checks will tell the story.
 
No smoke, ever.
 
knock that piece of crap out of the gap and run it some more. That plug looks too clean other than the particle in the gap. Like the previous posters, the first diagnostic tests should include a compression test and a leak down test. I would also throw in the basic "pull the #1 plug wire" test so see if you hear a difference at idle.
 
If they're fouling you may need to move to a higher heat range. You can tell if you have the right heat range by the colour change along the electrode. you should see a distinct change around the bend of the electrode. If the colour change is too close to the tip of the electrode, the heat range is too low, if its far beyond the bend in the elctrode, the heat range is too high. Have a google on "reading spark plugs"
 
I think you need to just drive it more :D
 
Warm it up at idle... then rev it at high RPM's. Watch the temp gauge if it works. Try to blow any carbons out the tail pipe. Your motor is essentially an air pump. Let it cool. Check the plugs again.

If it sat awhile, the gas may be bad. If not, it could be a combination of things.
 
How many miles total is on the wagon?
 
Drive it more, keep gas preservative in the tank and then drive it more. Then check the plugs and do a compression test because it looks to me you have different conditions in the cylinders.
 
Update...

Since I began this thread almost a year ago, the truck has been through a thorough tune up. Changed out those old plugs for iridiums(verified the gaps), but more importantly I think, it got a new custom exhaust system, new O2 sensors and a single CAT. The exhaust leak was before the cat, but now it's new from the head back. Perhaps the clogged exhaust/cat/bad O2 sensors was causing some kind of problem. There were other issues like fuel and filters, idle adjustments etc., but the truck runs better than new now, and the plugs are super clean. 12.5-13.5 mpg.
:bounce: I'm happy.
 

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