I just found out the stock spark plug for the box is standard copper plug - NGK V-power. I thought it should be at least the platinum but not.

My goal is to eleminate the gas smell from exhaust during warm-up and to improve gas milage.

now I think I should upgrade it with either Bosch P+4 or NGK Iridium. What would you suggest? :?: I know Bosch P+4 is easier to buy and it is about $6 each.

 

Stock plug is a Denso copper resistor type. Platinum's suck, Iridium is the only one I'd go with besides copper.

 

you wont eliminate the smell and as far as milage or power
dont bother the toyota engineers spent some time selecting
the proper spark plug for this application you can use whatever you want if it suits your needs i for shure would not
get bosch anything ive seen them fail many times on many different toyota vehicles also the plugs manufactured for
toyotas/hondas ect are of different quality than factory imo
dont waste your money/time

 

Thanks for your advices. I'll just go for Iridium. you know any local parts store carry them? I am Maryland. I just can't believe dirt built up on the copper plug tip, there is only 12K miles only on the car.

 

well if you want to clean 'em use a sand blaster to clean 'emup but make sure to blow all the sand out of 'em first before you install 'em back in

 

i hate to say it but theres a reason they have the plugs they do in our cars. platinum would not be effective in our cars since we dont have forced induction or high horsepower engines. my friends run iridiums and platinum but they all have performance vehicles where they have to have them. i would stay copper, but if you dislike them that much just change brands. bosch is a good company who I've had no problems with so i would recommend them too.

 

Denso iridiums. the one thing i really wanna say is never got bosch double , tripple or quad plug they fail. the ceramic insulator fails and the engine will not fire on that cylinder. my buddy with an old b16 blew 3 of em within a week . the weird part was they lasted like 6 months b4 they went bad but then all started going bad at approx the same time. we replaced em with cheap ___ autolite (i know crap) and didnt have a problem. one of those bosch double plugs did the same in my supra so i've been running denso iridiums in there.

 

I agree. Same issue with Neons...come with apparently cheap copper plugs, but all the news groups and users report they perform better than platinum etc. Just change them a little more often than the factory recommends, say at 15 or 20k instead of at 30k....

 

Copper is a better conductor, actually gold would be best

 

Why gold? Copper is a far better conductor than Gold. The reason they use gold in car audio, is mostly for bling and corrosion/tarnish prevention... Alot of people think that Gold is the best conductor, this is not true as Silver defines conductivity being the most electrically conductive metal on earth... anyhow, metals like silver and gold have a low melting point, therefore they would liquify in the combustion chambers.