I'm sure people are sick of me repeatedly posting....I see people say stay with OEM AC Delco plugs. None are available near me and would like to tune up ASAP since this H3 sat for about 6 months on the lot before I and the wife decided to love it. Bought some Quantum 4 spark plugs. Anyone have experience with these. Possibly another recommendation before I put them in on Saturday?

 

Order the ACDelcos on line, you are not in that big of a hurry, the I5s do not call for a plug change until 100K miles. Unless you like doing things twice?

 

Plugs don't go bad from sitting. Worry about fluids and filters but not plugs unless you are having rough idling (and I'd look at the MAF first anyway).

 

Changing plugs isn't really part of a "tune up" anymore. Plugs last 100,000 miles or more nowadays.
Things to look at are cleaning the throttle body & MAF sensor.

If you are intent on changing the plugs then they must be Iridium type, Do not use Bosch platinum.