Spark Plugs

[Cailen]

This has been covered before, but I thought it worthwhile to share my experience...

I bought this truck, and the previous owner said he had just replaced the plugs 10k ago, among other things (re oiling the K&N, etc). He said not to bother doing em as he had bought "the most expensive plugs", which turned out to be the bosch 4 prong plats.

You would not believe the difficulties I was having with this truck. Poor gas mileage, hard starts, and finally no start. And why? Because I was running on MAX 5 cylinders, more likely 4.

When I finally pulled the plugs (after replacing my spider and nut kit to no avail) I couldn't believe the condition they were in. All of the plugs were covered in black sooty crap, and two of them had major *chunks* of carbon between the electrode and the prongs. These chunks had the thickness of a CD and were as wide around as a pea.

So when people here recommend you use nothing but AC delco rapid fires or plats, listen. Now that I have the rapid fires in my truck its running great.

[Gabe25]

Another good reason not to run Bosch Plugs............

[MT-2500]

10-4 on that.
Factory OEM only hurts one time.
MT-2500

[BlazerBoyLT98]

Not that I would run anything but Ac Delco plugs but what is with the Bosch plugs running like shit in our engines? I used Bosch plugs on a jeep Cherokee I owned with just under 200,000 miles on it and thing purred like a kitten and was still powerful. I really liked that vehicles except for the god awful colors of the plaid interior!

[Cailen]

The jist of what I've gotten from other discussions is that we drive "expertly and finely tuned machines" that run like crap when you stick a plug in that's gapped differently / runs at a different temp than OEM.

[DINO55]

This is yet another story to be filed in the Bosch Garbage can...

[BlazerLT]

Yip, they just don't have any lifespan.