cjk09

94 cherokee sport 4.0l 240k miles put new plugs in not too long ago and pulled them to take a look and they are starting to turn white. What would cause this and what would be needed to fix this?

stock95sport(for now)

white on the electrodes usually means its running lean. the white indicates very high temps, which a lean condition creates. not sure thats what it is, but its likely

cjk09

ok... and what would some causes of that?

stock95sport(for now)

could be a number of things. If it is, for any reason, starving for fuel. I would say it could be injector related, but there are 6 injectors (one for ea cylinder) and normally one or two may be abd, clogged, etc at once, but not all of them. So if its all 6 plugs that are turning white, not those. also if its for some reason getting ridiculous amounts of air, to where the stock fuel system cant pump enough fuel to keep the air/fuel ratio around 14.7 would do it too. sorrry nott more help, but im sure someone will have dealt with this before and have some answers for ya!

Welcome to the forum BTW

Reece

I think white is good (clean burning). What color do you want them to be?

stock95sport(for now)

Well i assumed he meant the ground strap, which is not white to begin with. and to turn metal white requires some serious heat.... = no good.

check this out. good write-up.

http://www.angelfire.com/fl4/pontiac...Readplugs.html

cjk09

Yea, all of the plugs were white on the ends ... ill look around some more and see what i can come up with . Thanks for the info...and welcome haha

hankthetank

tan or beige looking

Jay420

My 92 Jeep does the same thing. Every couple weeks and the plugs are shot and turned white. Its obviously overheating somehow, but Ive yet to figure out the problem. Seems nobody here has dealt with this issue before.

Parsnip

Egr solenoid. It helps lower combustion temp by allowing exhaust gas into the air mixture, if its not workin right your buring at a higher temp- may not show up on your temp gauge but internally its combusting hotter then it should

stock95sport(for now)

Parsnip is dead on.

"The EGR valve controls a small passageway between the intake and exhaust manifolds. When the valve opens, intake vacuum draws exhaust through the valve. This dilutes the incoming air/fuel mixture and has a quenching effect on combustion temperatures which keeps NOX within acceptable limits. As an added benefit, it also reduces the engine's octane requirements which lessens the danger of detonation (spark knock)."

Parsnip

Its rare i hit a nail in the head like that lol

stock95sport(for now)

How's that saying go? "even a broken clock is right twice a day." lol

Jay420

Do non-renix Jeeps have an EGR valve???

Domaas

yes