The Truth About Spark Plugs....

I think I posted my update in the wrong thread. To keep it short, last night I changed my left side plugs and found they were NGK's while the rights were not. I'm thinking my truck had the original factory plugs still in it at 100k! Toyota apparently assembles with different plugs in each side. I read that somewhere on tacomaworld. They were worn but not too bad. If this is the case, that is pretty awesome for a non-iridium plug!

 

They did make then with different plugs on each side. Strange to me, but oh well. Most everyone that comes to my shop just asks to get NGK for their Toyota, no matter what is in them at the time. Never heard a single complaint from them since either.

 

Efficiency as in replacing, yes. Efficiency as in mileage, no. Also, as the plugs get higher and higher in mileage, will need to regap them to keep them in their most efficient range...

 

I beg to differ with you. I put 110K on my last set of Platinum plugs with no problem and the mileage was consistent from mile 1 until I replaced them.

I don’t make this statement based on my personal feelings or random tank mileage. I have a log (I maintain for both tax purposes and for personal history) in which I have recorded every fuel stop, oil changes and lubes, tire changes and all maintenance and parts since I picked it up new.

I don’t pull plugs to adjust the gap, if I’m going to do the work to remove the plugs I’ll just put new ones back in.

I replaced the Platinum plugs with Iridium the last time, so I’ll see if they last as long as the old Platinum ones did.

 

As we all can. By efficiency, meaning an increase in mpg over the standard plugs - which is no. My mileage has been consistent with the use of normal plugs, too. But others will know more though.

 

I didn't notice a bump in mileage when I changed to Platinum, my mileage increased until I hit about 40k and then it has held steady (not at a little over 190k). It's been a great truck, I swear that I wipe more oil off the dipstick checking the oil level than it uses between changes.

Other than the HVAC fan resistor and rear springs it's been solid.

 

When using platinum or Iridium plugs you do not ever need to remove and re-gap them. The older copper tips would wear, requiring a re-gap, but the platinum or iridium ones do not wear like the copper tips did. I have seen thousands of platinum plugs at 100k that were still perfectly gapped.

 

I'm thinking I should change the plugs in my new-to-me Tacoma, so I read this entire thread. It was both informative and entertaining. Obviously, I haven't changed the plugs on a Tacoma yet, so I was a bit concerned to hear it took an hour and a half for one poster to change them...and he didn't think that was bad! Hmmm, I've changed more spark plugs than I care to count, but the only time it took that long was on a V6 Corsica my wife had. I had to loosen the motor mounts and jack the engine forward to do the back three plugs on that crosswise, front wheel drive, little beast. Oh, and you couldn't actually SEE the plugs even then.

I certainly hope this won't be a similar experience. I also try to be economical (okay, I'm kind of a cheap bastard), so I did some tune-up math. O'Reilly Auto carries the NGK plugs for my 3.4 in both platinum and copper core. The coppers are $4.99 each. The platinums are $10.99 each. So, assuming a 30k mile change with the coppers, 90k miles would mean $89.82 worth of plugs. On the other hand, the platinums would theoretically last 100k miles and cost $65.94. Add to this the potential for 4.5 hours of labor versus 1.5 hours, and the platinums start to make sense to me, particularly if the performance is equal over the lifetime of either type of plug.

Does this sound about right?

 

I used the NGK iridium plugs the 2nd time around. They are a 100k plug. Runs like new. About 25K on iridium plugs now. See my other posts for further detail. Why would I waste my time, money and inconvenience myself to have plugs replaced at 30K, ridiculous. Toyota dealers looking for your money!

 

Yeah, that's kind of my take on it too. They will be looking a long time to get my money though...service and maintenance happens in my garage!

 

https://www.youtube.com/watch?v=fYh_qiMKZ3k

 

What's your point?

 

When i purchased my new to me Tacoma I serviced the diffs, T-case, synthetic motor oil, fuel system cleaner, and Denso plugs with the ones Toyota recommends, and air filter replacements. I do all service on any used vehicle I buy, in this case my Tacoma had 38k miles. My question is I am at 50k miles and drive mostly city stop and go should I replace them its been 12k miles. I mean they are cheap enough and easy to do. I also own a Mustang Cobra and I know many who replace the plugs every other oil change .

 

If it makes you feel better to replace them, then go ahead, the recomended interval is 30k. Maybe do it when your odometer reaches 60k and see how you make out.

 

good call. 20k it is.

 

sorry to revive a dead thread, but what is it that they sell at the dealerships? the NGK's or the Denso? I'm guessing Denso.

 

I just picked up 4 plugs for my 98' 2.7 from the dealer for $2.22 each. At that price it wouldn't make any sense to not buy the oem plugs straight from the dealer. Part# 90919-01176 & on the actual Denso plugs it says K16R-U.

 

denso

 

When I bought mine with 120,000 on it I put in NGK iridiums. Only because they last so long. I'll pull them at 50,000 and see how they look. I suspect copper is a better performer but I like the idea of less maintenance. They seem to work fine for me so far with 20,000 on them.