Highland Runner

I put the +4's in my 95 Tacoma(2.7) and my 94 Runner a couple years ago. They were only in a couple months, and both started running bad and getting bad mileage. I pulled a plug on my 3.0 and it looked even worse than those above. They were covered with a thick white ash. The 2.7's plugs didn't look that bad but the engine missed badly. Replaced plugs in both engines with stock plugs and both were fine. BTW, the stock plugs I originally took out of both engines looked to have normal wear and had been in for a LONG time.
A master mechanic I know said the plug gap on the +4's is too much for the stock ignition/coil. He said you should never use these on Toyota's although it seems some people never had a problem.

X-AWDriver

Expensive plugs aren't going to do anything with the stock ignition backing them on a 4Runner.
My friend has a 700+ crankhorse Supra and he runs $3 NGKs and it runs great. Also remember platinum isn't the greatest conductor of electricity so they shouldn't be used on forced induction engines where high boost pressures are present but platinum is fine on everyday engines since it is good for longevity.

Ilovemountains

I had the +4s in my 3.0 also and it ran like crap, the people at the local parts store told me to get them out asap! I switched to regular Bosch platinums and it runs better, starts better and seems to have more power now! Just a thought!

Bumpin' Yota

Another interesting tid bit is when I went to toyota to get my plug wires, rotor, and cap, they emphatically stated that I NOT run ANY bosche plugs....I said dont worry I have some Denso's ready to go in.

kyle_22r

i think double/quad elecrode plugs are a worthless gimmick. if you think about it, the spark is only going to arc to one electrode, so you get more surface to gunk up on the other 3

i used to run bosch single platinums in my old 2wd yota and they worked fine for the most part, but i'd have some missing occasionally and my tach would jump around under hard acceleration.

keisur

that's because they don't sell Bosche plugs.

splitz

Well, it looks like I've bought into the hype. I replaced my plugs about 2 months ago; now I'm going to check my plugs to see if any build-up is forming.

Melt

˟˟˟˟ i put some of these plugs in my accord a few months cause i was gettin like 20mpg highway, and after i replaced em it stayed the same then got worse, im talking 18mpg out of a 4cyl ... i replaced the o2 sensor and its up to 22 HIGHWAY!!!! I used to get 27 with my mtn bike on the roof goin to tahoe! .... i better pull em and check whats up

I think honda uses either denzo or ngks for the stock plugs.

bike4miles

Thanks for hte info. I'm sticking with NGK

Bumpin' Yota

I went to nippen denso double platinums with the dual ground to replace those POS bosches - pulled em after 30k when I did my timing belt/thermostat/water pump/belts/hoses/timing idlers and they look GREAT!

I also reset my base timing to 10* BTDC where as the old setting was at 15*. Oddly enough I still get intermittent ping even on good 93 octane gas. I think its just the wire on the knock sensor though....I need to ground the sheild on the knock sensor wire to clean up most of the interfierence that they tend to pick up...

so those plugs could have been caused by detonation and/or by pig rich operation. The first 1/2 of their lives was under a stupid rich condition with the o2 sensor completely shot...

2001Millrunner

I've heard Champions are really good, no?

Troymm

I've got the IK20's which is one step colder than stock, and its running great so far.

Tacotex

Think of Bosch plugs and Toyotas like oil and water-they don't mix. Heard this from more than one pro as well. I've been using NGKs for over 20 years and have no plans to use anything else. The factory manual for my '93 DX listed both Denso and NGK part #s.

86toyota

Have you ran fuel cleaners too many times lately? Looks like that was the cause of all that ash buildup.

Melt

just picked up some ngk vpowers at kragen for my accord! Ill post pics of how fowled my bosches are if thats my problem.

OMINOUS_87

NGK.....................................

cubuff4runner

I had the same thing happen when I ran 4+ a few years back. I would never run anything other than NGK or Denso. Nobody has ever said that they have had a noticable positive change when switching to a plug other than ngk or denso so why change and risk damage?

keisur

I picked up some Denso's yesterday for my tune up I'll be doing soon. I think I have NGK's in there now.

gwhayduke

I must be the only guy in America that hasn't had bad luck with Bosch.

Bumpin' Yota

Have ya pulled em just to see lately?