So have been battling with cylinder #8 for quite some time now, and looking for input. Valve seal recently replaced on #8, was leaking. Now seem to be going through the plugs, the first couple were melted into nothing, now seems as though that hole is running lean. Reason being, the plug is whiter then white.

Have recently just changed the injector, have not checked plug since, so not entirely sure if that fixed it yet, looking for other suggestions.

One person suggested cats, but Im having trouble seeing that as its not an entire bank issue, just the one hole.

Other possible issue im thinking is poor coolant flow in block in that particular area, and not entirely sure if a coolant flush and fill will remedy it.

Any input greatly appreciated. Also, did do a search, didnt turn up anything, hoping this isn't a common known issue or something stupid.

 

No thoughts ?

 

Blown plenum which leads to a clogged cat causing your #8 cylinder to have some issues. Could eventually end up with cracked heads

 

Yeah, need to check plenum, and cat.... Federal, or California emissions?

 

Like the other guys said check the cat. The #8 cylinder/plug is the closest one to the heat of a clogged cat.

 

You could try the trick I recently saw on youtube... pour a gallon of laquer thinner in with a half tank of gas and run it at about 2,500 rpm for 30 mins and it should help clean out a plugged cat.... usually a blown plenum would cause #8 problems but I believe you would get soot from burning oil if that were the case....I would suspect it was your injector...I have a mis on #1` under load and found there are little fuel screens for each injector and mine seem to be plugged with a black substance which may be the fuel line breaking down...

 

I seafoamed my engine (my 1996) and there was A LOT of carbon coming out of the echaust...we are talking FLAKES.

YOu could try using seafoam to see if that helps. Pull the wire on the #8 cylinder so some of the seafoam mist gets into the cat. it might help.

I would rather use seafoam than laquer thinner, although both the compounds might have the same properties if they aren't the same compounds.

 

CHECK THIS:

If you have a 1994-1997 you have EV1 injector connectors. The square ones with the very thin tiny metal clip around the plastic connector. If that thin clip is missing, then you will get a miss on that injector. It will not be a consistent miss either. It could be completely NOT firing or sporadic.

Check to see that all your connectors have clips. If you have a 1998-2001 then you have EV6 connectors with the red lick tabs and you should not have to worry. Howver, it could be the injector connectors. they get loose and they won't bite on the male prongs in the injectors.

 

Replaced the injector and re checked the plug on #8 today - white as a ghost. Only 2 options left I can think of, bad cat or cracked head issue, sucking too much air on intake stroke.

 

Nope, only the red click tabs