I replaced my spark plugs about 1000 miles ago, looks like it might be an incorrect heat range, they are champions. Does it look fine to you guys?

 

Champion platinums?

 

Just champions

 

There's your problem. Champ Plats are OEM replacement with the proper heat range. You need to change your plugs to the Champion Platinum plug with a .040 on the gap. Make sure you double check the gap. Although some say gapping not required, I almost promise you the gap is always off by about .02 degrees

 

Thank you man, glad you helped me out, hopefully i can return the favor.

 

No problem bud. I've had my rig about 5 years, kept her in my divorce and I used to own the L6 4.0 so I've learned a few things over the time.

 

Champion plugs always had the reputation of being gapped for the intended application, but I always check. sometimes in shipping, they get banged around. Champs have the extended tip to get the fire out into the chamber for better burning, but they run hot because of that, so the heat range is critical. I've run Champs in my GM cars, but you have to use one heat range colder or they'll fry.