web

Anyone have any particular suggestion for spark plug "upgrade" for the NA tC or if that would even be worth doing?

nodsetse

Definitely not worth doing. The stock plugs are iridium and are spec'd to last 120k miles, so I don't know what anyone could "upgrade" to.

web

Good call, thanks.

terra_tC

you already have the best out there....

Revilo

the only time you can upgrade them, if only when you go FI... to a colder ones

web

Agreed. Cool, thanks again all. Just seeing what else is out there for our cars, that's all.

HP_Pirate

iriduim power baby............the best of the best at least for now.

thank you toyota.

2AZ-FEtC

Factory Denso coil packs with Denso Iridium IK-20 plugs work very well (Denso +Denso = goodness) .

Factory Denso Coil Packs with OEM NGK Iridium plugs sometimes doesn't make sense when you think about it..... Maybe Toyota was on a budget and went with NGK, since it's sheaper then Denso Iridium Plugs.

All in all, Iridium plugs are the same in comparison except for the cooler burning plugs, so it's your choice. Cooler burning plugs are good for boosted motors.

I've always liked Denso. Denso just seems to be Toyota and NGK Honda, but this is my thinking.

Also, if you put a Denso and NGK Iridium plug next to each other, the Denso looks and feels better quality.

2AZ-FEtC

Actually, Iridium plugs should last about 50,000 - 60,000 miles before changing them. Iridiums aren't bullet proof, they just last about 20,000 - 30,000 miles longer then standard plugs. You can get 90,000 miles out of them, but poor performance and low gas miles.

dp-_-

1) we have denso's, not NGK's in our car
2) they are rated for 100k or so miles
3) I know a guy that works for Denso and I was looking for better plugs only to get a call back saying, "dude, you have better plugs that I can even get. We don't carry them here."

web

The whole rating by the dealership for length of life for our plugs is sketchy. They might get those numbers from the manufacturers but I highly doubt those are numbers that would justify the driving of some tC owners. I'm sure the average length of a standard plug is between 35-60K and Iridium would be between 60-100K. I would never just wait until 100K and then say, "Ok, time to change them." At 12$ a pop, they aren't dreadfully bad since we only have 4. My '96 Ranger was an I4 but took 8 plugs!!! Intake and exhaust combustion (more efficient fuel consumption). I ran motorcraft in there that were rated at 100K by Ford, but I changed them out at 70K and they were pretty dark tan, getting closer to black without any oil leakage from the seals.

It's kind of like oil changes.....everyone has their opinion about when it should be changed and what type you should use. It eventually comes down to personal preference and the understanding that ALL oil has a breakdown point and lifespan. It's up to you to change it prior to it reaching that point.

2AZ-FEtC

1) LOL..... Pull one out and find out.....

2) 100k miles were did you read that, boy I want some of these.

3)Your buddy should be fired for lack of knowledge. I replaced my stock NGKs with Denso IK-20.

web

There are tune up intervals rated at 100K, and some companies claim that for their spark plugs (Motorcraft for example), but I still would change them at 60K or earlier, just like oil....instead of synthetic being able to last for 6-10K, I'll still change mine between 3-4K (Amsoil).

2AZ-FEtC

I agree 100%. I still change my plugs around 30 - 40k and my syn oil comes out around the same time 3-4k.

When I pulled out my stock NGK's the center electrodes were decreased significantly even after 25k. After the change with brand new Denso plugs she idled and ran better, like new.

web

So what is in our stock? It's kind of hard to ask this since "stock tires" on most sites say Bridgestones and mine are Yoko. I would assume Denso would be stock since dealer specs for newer Camry's and Corollas are those Denso plugs with the U-shaped bar.

2AZ-FEtC

NGK OE Laser Iridium IFR6T11 Part#4589 Gap 0.044 were in my car stock. It's possible that Toyota put in Denso in some tCs.

My previous car which was a 2000 Celica GT-S had the same NGK plugs as well, which stumps me a little bit since Toyota uses Denso Coil Packs.

web

Yeah, I used to work at a parts store for 3 years and all the Toyotas that came in always requested the Densos. So, not sure. I guess I'll have to check. I've got 14500K on mine so i'm good for a little bit.

2AZ-FEtC

It doesn't hurt to pull one out and have a little peek. I was shocked myself to see NGKs again for the 2nd time in a Toyota motor with Denso Coil Packs. I can garantee you have NGK as well.

nodsetse

For plug life, I was simply stating what I recall from the recommended maintenence section of the owner's manual.

Personally, I don't feel plugs should necessarily be replaced at a set interval as you've suggested. Even though they're not too expensive, I'd rather pull them, clean, regap and test periodically, and only replace the set when one plug's performance becomes suspect.

Dr_Isotope

iTrader: (1)

Side note: any synth oil change below 5k miles is just money down the toilet. I change every 7500, which is just about the minimum service interval for quality synthetic. If you want to do 3-4k changes, switch back to dino and save 2 bucks a quart.