When to change Sparkplugs

[base11]

Hi
I'm the guy with the rear head gasket leak, which I am getting fixed at the dealer. G.M. is paying for half on a good will gesture.

I thought I would have them change the spark plugs and wires seeing as the engine is so accessible and maybe they would give me a break on the price. I just checked the manual and this is recomended at 150,000 kms. and I only have 70 k on mine. Living in Canada I think just getting the plugs out after 7 or 8 years would be a challenge let alone waiting that long to replace them.

What do you think? Shoud I change them now or save my money for now and change them in the future when they actually need it. I wont be doing it myself, to hard to get at on this vehicle for me.

thanks

[AJT1961]

Head gasket failure usually causes some fouling of plugs in the affected cylinders, so it's not a bad idea to have the plugs changed IF they give you a well-deserved break on the labor charge since they are ripping apart the engine anyway. I had the gasket problem at around 60,000 miles and had my first plug and wire change at around 110,000 miles. Before the plug/wire change, I had a few episodes of rough idling which was rapidly cured with a $5 (US) bottle of high quality one-time super high concentrated fuel injector cleaner, which will also remove a good deal of plug fouling.