96 LX450 P306 code

[nryke]

Some one said that it may be the beginning of head gasket failure and posted a picture of the damaged HG. If the HG is the reason for the P306 code, the engine would run rough all the time, doesn’t it?.
My LX450 runs ok after I clean the spark plug (dry, black soot) and after a few miles it starts missing again.
Any thoughts?

 

[scottryana]

Doubt it is a headgasket. That would mean a fairly clean plug do to steam cleaning the cylinder.

It looks rich, like unburnt fuel. I agree with earlier posters that there is a reason that plug isn't firing.

 

[inkpot]

Either a sticky injector or inconsistent spark. Trouble shoot for those.

 

[nryke]

Doubt it is a headgasket. That would mean a fairly clean plug do to steam cleaning the cylinder.

It looks rich, like unburnt fuel. I agree with earlier posters that there is a reason that plug isn't firing.

 

[nryke]

Agree, will swap injectors tomorrow and report back the results.

 

[nryke]

Either a sticky injector or inconsistent spark. Trouble shoot for those.

Thank you Inkpot.
I will install (borrow from my other 80’s) a different injector that was working and report back the results.