Spark Plugs
Cailen
11-07-2005, 12:41 PM
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.
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
11-07-2005, 03:52 PM
Another good reason not to run Bosch Plugs............
MT-2500
11-07-2005, 03:59 PM
10-4 on that.
Factory OEM only hurts one time.
MT-2500
Factory OEM only hurts one time.
MT-2500
BlazerBoyLT98
11-07-2005, 04:00 PM
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
11-07-2005, 05:06 PM
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
11-07-2005, 09:28 PM
This is yet another story to be filed in the Bosch Garbage can...
BlazerLT
11-07-2005, 09:37 PM
Yip, they just don't have any lifespan.
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