Chevrolet Repair: spark plug wires/sludge, valve cover gasket, chevy lumina

Question
could you please tell me what is the correct spark plug wire sequence on a 98 chevy lumina?, and...also, why the middle spark plug of the ones on the fire wall side came out with a lot of sludge?

Answer
Hi Jorge,

I found this question in the trash can of questions.  Once the orginal expert throws it away, any of us can answer it.  I hope this helps.

The firing order can be found on Autozone.com.

The sludge is on the outside of the plug hole, or on the actual tip of the plug?  

IF on the outside of the cylinder, it is something leaking and driping into the plug hole.  Gets hot and boils off the moisture.  Probably a valve cover gasket, but not necessarily.  

If inside the cylinger and on the tip, look for a bad plug wire.  Could also be a coil failure.  Could be leaky injector.  

Hope this helps.

C J S