Pointy spark plugs

Hi,

Am performing tune-up on my 2000 Yukon. Already changed the plugs/wires, PCV, checked EGR valve and replaced air filter.

On the plugs, they (AC Delco plats in there about 30K miles), they are worn down to a very pointy nub. My book says they may not be the right heat range or maybe there is debris flying around but I doubt that. The insulator is ash white. Put in new Bosch plats. THoughts?

Still to do:

Replace all 4 O2 sensors. Any hints on this?

Replace fuel filter. Book calls for me to release the fuel pressure and use a hose, etc. Do I have to do this?

THanks!

AC plats do have a narrow diameter center electrode, no sure what yours looked like but I would not use Bosch in that truck. You can pull the fuel pump fuse and run the engien till it quits to relieve most of the pressure.

Hi,

Am performing tune-up on my 2000 Yukon. Already changed the plugs/wires, PCV, checked EGR valve and replaced air filter.

On the plugs, they (AC Delco plats in there about 30K miles), they are worn down to a very pointy nub. My book says they may not be the right heat range or maybe there is debris flying around but I doubt that. The insulator is ash white. Put in new Bosch plats. THoughts?

Still to do:

Replace all 4 O2 sensors. Any hints on this?

Replace fuel filter. Book calls for me to release the fuel pressure and use a hose, etc. Do I have to do this?

THanks!

If they were platinum plugs, the gap might be ok even if there is significant wear on the centre electrode.