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Replacing Spark Plugs and cleaning fuel injectors

I have a 2008 Toyota 4-Runner with a V-6 engine. The manual and the Toyota garage tell me I should replace the spark plugs and have my fuel injectors cleaned every 30,000 miles. I thought with today’s modern fuel-injected engines, the spark plugs should last 90,000 miles. In fact the service representative told me that the V-8 engine spark plugs do last 90,000 miles. As to cleaning the fuel injectors, I use only name-brand gasoline with detergents etc. (Chevron with Techroline). Why would my spark plugs need replacing and my fuel injectors need cleaning at 30,000 miles?

Your owners manual should contain a service schedule. Most cars NEVER need to have their injectors cleaned and MANY cars go 100K miles on a set of spark plugs…The person you talk to at the Toyota Garage is called a “Service Writer” and most of them are commission salesmen who know little about cars…

The spark plug may indeed remain clean in modern clean burning cars, but the gaps often increase about 1/1000" per 1000 miles. If the gap gets out of tolerance, the engine might start to ping or it might not pass smog. An out of tolerance gap can also stress the coil and the wires which can lead to failure of parts more expensive than the plugs. Unless you have a plug that resists this gap increase, I think 90K is a little too long to wait to change the plugs. I’d use the interval that the owner’s manual says. Replacing the plugs isn’t that expensive.

On my 1990’s Corolla, I change the plugs every three years, which is around 30K. The plugs specified for the car (NGK) cost less than $2 each, and I can easily do the job myself in about 30 minutes. Trying to save money on spark plugs is probably penny wise and pound foolish.

You can save money on the injector cleaning in my opinion – by not doing it. I wouldn’t ever clean the injectors unless there’s a problem with the engine performance that indicates this is necessary (which seldom occurs) or the car’s owner’s manual specifically recommends injector cleaning.

This 2008 vehicle uses conventional plugs? I’m surprised. I guess it’s a truck thing.

Platinum and iridium plugs last much longer than 30k miles.
Has nothing to do with fuel injection.

As always, I recommend you stick with the same type plugs the engine came with from the factory.

We have a 2003 Toyota 4Runner with the V-6 engine. I think manual for our 4Runner calls for a plug change at 60,000 miles. The V-8 called for a less frequent plug change. However, there is an advantage to the more frequent plug maintenance. It is less likely that the plugs will seize in the cylinder head. The engine in the 4Runner is comparatively easy to change the plugs, so it is worth doing.
The manual for our 4Runner does not call for an injector cleaning. If your 4Runner is running well, don’t do the injector cleaning.

my car calls for plugs at 100k i’m changeng them every 50k no problems so far.132k now on the od. no problems at all knock on wood.

Make sure the manual matches what the Toyota garage says. If they are standard plugs, 60k (or much later depending on driving habits) is soon enough and iridium tipped plugs should easily go over 100k. I had this run around with my dealer till I got them to admit that maybe 30k (even 60k) was too soon…do ya think ?

As far as injector cleaning is concerned, consider it only if you let ethanol lased gas sit in your vehicle for weeks at a time. Otherwise, they should be problem free. Again, compare the manual to the dealer bonus you are supplying them. They and suppliers make their profits on extra unneeded service.

I agree with Triedag and GeaorgeSanJose about seizing and gapping plugs and suggest they be “checked” at 60K, even iridium.

Bottom line…don’t let the dealer read the owners manual for you.

My '01 Toyota Sequoia (V8) calls for new plugs every 30K miles in the maintenance manual. Not sure why, but it is simple and a DIY for me. I don’t buy that the 30K fuel injection cleaning is given in the factory maintenance guide. This sounds like a “dealer recommendation” item to me.

You can pull a plug and take a look. I’ll buy the OEM replacement plugs and DIY. The coils pop off the plugs easily and this a simple job. Use anti-sieze compound on the threads of the new plugs as you install them. Dialectric grease on the ceramic tips of the new plugs is a good move too. Forget the FI cleaning and you’ll be fine and save a few hundred $$$. The plugs aren’t expensive, about $5.00 ea.

I just looked at the owner’s manual (on Toyota’s website) and was very surprised to see the interval for plug replacement for the 2008 4-Runner with the 1GR-FE engine (v6) was 30,000 miles - independent of severe service.

I would have thought by 2008 they would have used a longer life plug.