Bosch plugs 4 or 2 prong

[gmbwrenchn]

Have a 97 Blazer 135k Miles. 4.3ltr. Is there really any difference in performance, milage, etc. with the Bosch 2 prong or 4 prong plug? Thanks.

[GreyGoose006]

well i woulnt use bosch plugs on a blazer
not only wouldnt i use them on a blazer, but i wouldnt use them at all.
they have a reputation of the ceramics cracking inside the engine

BUT

if you insist on using them, i doubt that there is much difference except for price

[UncleBob]

specifically, never use "platinum plus" bosch plugs. They are the worse plugs on the planet

[GreyGoose006]

so it isnt just a myth then.
i considered using them once, and the kid at napa refused to sell them to me

[2.2 Straight six]

they're terrible plugs.

i've known people install them and have misfires and all kinds of issues.

chucked them away, put in some NGKs and it was all good.

[gmbwrenchn]

Thanks for all the info. So NGKS are pretty good to use on my Blazer? Who has those plugs? Thanks again.

[dave92cherokee]

Stay away from the bosch plugs, I installed a set of the platinum plus 2's in my 92 cherokee within 50 miles the ceramic and dielectric in one of them broke off inside the cylinder and beat the piston to crap, scratched the cylinder wall, before finally being pulverized enough and causing enough damage to be ejected through the exhaust. Had to do a complete engine rebuild on it including having the cylinder bored out and sleeved to get it running again. When I called bosch to see if their warranty covered the damage done to my vehicle they said that I would have to send in the plug, receipts for everything, and they would examine the plug to see if it was a faulty plug or if they could blame it on something else.

[curtis73]

The best spark is the most consistent spark. That can't be achieved with fancy 2 or 4 prong plugs. Stick with normal plugs that aren't trying to sell you a gimmick. Put it this way, if a plug has more than one electrode and has some kind of ad at your local parts store, skip it.

AC Delco
NGK
Bosch Platinum

Period. Unless you're seriously modified, a premium stock replacement is the best plug.

[TexasGuy]

Don't know, I got the 4 prong platinum for my Chevy Lumina Van, work well for 2 years. When I got them changed to, felt a huge increase in performance. Next change it is Bosch for me.

[turtlecrxsi]

I used the Bosch +2s once in my crx. It seemed as if I had better mpg but the spark inconsistency was embarrassing... snap, crackle, rice. I put NGK's back in and had noticed consistent spark across the rpm range and no more snap crackle crap either.

I am using Champion plugs in my Jeep. I have a head Dodge/Chrysler/Jeep technician in the family that swears by them and that's what the factory installed originally so that works for me.

Like Curtis said, avoid the gimmicks because all they really sell is bs...

[gmbwrenchn]

Thanks a lot for all the info!!