I went and bought some BOSCH platinum sparkplugs the kind withe just one tip. Anyway when I put them in my truck it ran horrible. The service engine soon light started blinking which I think means MISFIRE? Well no power no get up and go just alot of sputtering and backfire? I took them out and replaced w/old plugs AC DELCO and it ran fine. Anybody else had this prob.? They are suppost to be good plugs. Also any advice on what plugs to get? Since the BOSCH were no workie. OH yeah its a 99 nbs x-cab Z71 5.3L
Thanks

 

bosch suck dude i had the same problems.ended up with ngk tr55ix plugs and i can say they work fine

 

I just installed TR55s $1.40 each,I may have the placebo effect but the fkr seems to idle better.I wanted TR55iX i would have had to order them and they wanted $8 and change each. Someone here said $5 from Orileys,i tried there website and couldnt get Jack for information,i must have to register inorder to see there cataloge.Any comments about this?

 

why chang your stock spark plugs what are you gaining

 

my towing fuel mileage took a dump,this was easy to try ,i know the odds are slim that it will have an effect.