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Toyota Camry spark plugs

I have a 2004 Camry with only 34K mileage. The dealership is recommending replacing the original spark plugs. I want to do the reasonable, responsible maintenance on the vehicle…should I have the plugs replaced?

No, spark plugs ao not have a time replacement requirement. Go with the schedule in your owners manual Since the car is driven only 3400 miles a year, use thr severe service schedule…

When you do get the plugs done stick to the plugs listed in the owners manual. I have had 5 Camrys since 1987 and never had a problem with plugs that way. I have had problems using different than recommended.

Regardless of the mileage. plugs that have been in the engine for ten years should at least be taken out to make sure they don’t become permanent plugs. As long as they are out, might as well pop for the extra $30 for new ones.

I’ll go with Bing on this. He made a good point about the plugs becoming permanently married to the engine if one leaves them in forever.

Except that I never reinstall old plugs in most cars. Camrys, like many other cars, have flat seats with crushable metal washers at the base. The washers actually made more like a hollow metal bagel, they are not a solid metal piece. The crushing of that washer upon installation seals the seat. Once crushed, the washer cannot then be recrushed to form a correct seal. It is, admittedly, a small point, but that’s my philosophy. Plugs are cheap. Never reuse old plugs.

Oh, and a Camry will not respond well to anything but NGK or Nippon-Denso replacements. Those are the the OEM suppliers to Toyota. And for a 2004 I strongly recommend iridium center electrodes. The parts store will offer options, but iridium is the way to go. Irridium is 8x harder than platinum, and in addition to eroding far more slowly the center electrodes are much smaller diameter, providing a more focused spark.

I kind of have to agree about changing them. The factory plugs do come with a very good anti-seize plating on them, but time will take its toll. I also would not put the back in not only because for the seal, but also you damage the plating taking them out and reinstalling them and in some cases, using an anti-seize paste will not be compatible with the plating and cause issues.

But on the other hand, if you leave them and they do seize, they will still work for 120k miles or more and at the rate you put on mileage, that would be a very long time indeed. It could become an issue for the next owner if you ever trade it, but thats not your problem.

Worse case is that they have already started to seize and if you replace them now, you could end up with a big bill for cylinder head repair, where if you do nothing, the plugs will be good for another 30 years with no problems at the rate you drive it. My limited experience with the factory plugs in the Toyota is that they will not be seized at this time and will come out very easily.

I have never had a problem with Toyota plugs either, but agree that it’s prudent to change them.
In my admittedly limited experience, the plugs that tend to seize are the ones with the conical bases rather than the flat/washered bases.

How much do they want to charge your for this? If it was my car, I’d just replace them - but I wouldn’t be paying a dealer to do it.

The plug gap will widen with miles driven and will eventually cause problems. And if you wait too many years, the plugs’ threads can seize to the head and the head can be damaged extracting them, which is not a good thing, expensive to fix. For what it is worth, I try to change the plugs on my early 90’s Corolla at 30 K intervals. Sometimes I neglect this, but last time it got to about 50 K and I developed some pinging which forced the issue. The plugs I took out, the gap was too wide, well outside of spec.

It’s critical that the replacement plug be one recommended in the owner’s manual. Usually the manual will list 2 or 3 by part number that meet Toyota’s specs for the car. Sometimes shops will put in a plug they think is compatible, b/c the spec’d one isn’t available and would need to be ordered from the parts warehouse. In my experience it’s worth the wait to get the exact plug spec’d for your car. If it takes 2 weeks to order them, then it takes 2 weeks. I’ve always used the NGK exact replacement plug on my Corolla and never had a problem in 20 years.

As far as your car, newer cars are using special plugs that last more miles, and are more resistant to thread seizing. But at 10 years it’s probably a good idea to change them out. Ask the shop if they recommend to use a little dab of anti-seize compound on the threads to prevent problems next time.

I wholeheartedly agree that only OEM replacements should be used.

I should point out that databases at parts stores will generally list copper core, platinum, and iridium plugs even for cars that came with iridium plugs. Often they’ll also offer what I call “magic” plugs; bifurcated (two forked), trifurcated (three forked) and sometimes other fancy gimmicks. Avoid these.

Your 2004 Camry came with iridium tipped EKG or Denso plugs. I strongly recommend using nothing else.