Spark Plug Buildup (more Info Inside)

[LilBerx]

Well, I bought a car a few months ago, guy told me it had a bad valve seal.
In the #8 cylinder
Car was smokey on really hard acceleration (above 3k)
Plug was getting buildup on the edge.
Two days ago I ripped it down to swap the Intake pulled the valve covers, compressed the springs, pulled them off, and put on a new valve seal and threw it bak together. Valve guides were fine

Today I threw new plugs in, and it runs damn good!! But I pulled the #8 plug and its getting buildup still, on hard acceleration it doesn't smoke as much, but still does.

A few weeks ago I ran a compression test, and it was reading 135-160 all the way around (160 in #8 cylinder)

I am trying to narrow it down to what it could be. So far I've eliminated, bad rings, valve seals, head gasket.

What else could it be?

Could it possibly be buildup that is still in the cylinder that is still burning out from te bad valve seal?

Please chime in, I would appreciate it.

 

[stykthyn]

leaky injector?

 

[LilBerx]

Would that cause buildup on the end of that plug?... It's more of an oily buildup, I'll try and posted a picture.

 

[LilBerx]

 

[stykthyn]

looks like you are running way lean

 

[LilBerx]

The gap was **** up on my plugs, I put all new ones in today and gapped at .049

 

[LilBerx]

Kinda dead but I have updates.

Like a person above mentioned, a leaky injector, well I swapped injectors and still buildup.

I also heard of blowby through the intake, so I added a oil separator from the PCV valve to the intake. It is collecting little to no oil.

I am still getting buildup... Any other ideas?

 

[stykthyn]

blowby is a sign of worn rings. may explain the oily build up.

 

[LilBerx]

blowby is a sign of worn rings. may explain the oily build up.

How could it be rings if my compression test came back good?... 165 on the cylinder that is getting buildup.

 

[srtthis]

looks like you are running way lean

you cant read plugs after youve idled on them...
unless thats a wide open throttle pull then the motor shut off while at wipe open throttle you will NEVER get a good reading on a plug.

as for the oil left over on the plug... give it a few days of running with the plugs in it and let number 8 burn what ever is left in it out. and then report back. may help to pull them out after 2 or so and clean number 8 off so you know its getting a good spark in that hole.
might also want to run some seafoam through the PCV line to break up any crap thats down in the chamber also to help get it out.