Spark Plugs

[41magsnub]

Teach me about spark plugs...  I have a 1999 Toyota Avalon for my daily driver with 85K miles on it on the original plugs.  It is about time to replace them right?  I've never swapped plugs in anything bigger than lawn and snow equipment...  I poked around and I see how to get to each of the plugs, no big deal there.  I'll just do them one at a time to make sure I don't screw up.

Assuming that is the case, what should I get?  Using O'Reilly auto parts as an example they have regular copper core plugs for $2 each up to some "laser platinum" plugs for $10 each with everything in between.  Are the ultra fancy plus worth more $$$ or is it a gimmick like monster cables?

[Harold Tuttle]

kinda gimicky but spending 20-50 bucks every 85K miles is cheap

check the old plugs for diagnostics

http://www.centuryperformance.com/spark-plug-reading-spg-192.html

[taurusowner]

Teach you about spark plugs eh?  Well small shards of them are very useful at shattering auto glass lol.  I'm afraid that's about all I know.

[bedlamite]

In my experience, either get the cheap Autolite plugs and replace them every 30K miles, or spend more and get the NGK IX plugs that actually do last 100K miles. Bosch Platinum actually use Yttrium for the electrode, and while they are better than other platinum plugs, they don't last long enough to make up for the extra cost. Two brands I would avoid are Champion and Denso.

It's probably obvious, but I'll mention it anyway, use Anti-Seize on the threads.

[41magsnub]

Thanks guys!

[Bigjake]

NGK plugs FTW...

Just make sure your gap is correct, and that's all there is to it.

Oh and I'm jealous as hell that your plugs are easy to reach.  Plugs on my wife's truck have me disassembling half the bloody engine!

[41magsnub]

NGK plugs FTW...

Just make sure your gap is correct, and that's all there is to it.

Oh and I'm jealous as hell that your plugs are easy to reach.  Plugs on my wife's truck have me disassembling half the bloody engine!

The 3 in the back are going to be a minor hassle but with an extension and a flex joint I should be able to get the socket wrench on it.

At least I still have the set of feeler gauges I bought for auto mechanics in high school oh so many years ago!

[never_retreat]

I used to use the Bosch platinums when I owned vehicles that used spark plugs. They seamed good.

[sanglant]

if there is a car forum for your car(like this), you can see whats working for other owners. the ngk ixs lowered the idle on my car by just over a hundred rpm. i stay away from the platinums had the little disks fall off one set(bosch). talk about some bad mileage.

[Nick1911]

I've done plugs in quite a few cars and trucks over the years.

Some things I've learned:

• A lot of gimmicky crap is just that.
• NGK's are overall very good, but:
• I've been really hard pressed to find a better after-market plug then the OEM one's.
• I change ignition wires at the same time.  It seems that tend to be brittle and crack when moving them around.  Out of all the plug wires, none are as good as OEM, in my experience.  Hey, the ones that are on there are still going after 85k, right?
• Do use anti-seize, especially in an aluminum head.
• If you don't have a good feel for it, use a torque wrench when reinstalling them.  Then you can have confidence that the plugs are installed correctly and you won't risk stripping out the head by overtightening. 

I seem to recall my Dad saying that the OEM brand for his Toyota is NGK, this info should be listed in your owners manual.  Certainly worth taking a peak at, IMO.  Personally, since I'm running an all-Ford fleet these days, OEM = Motorcraft for me.

[Jim147]

As has already been said. Check what the OEM plugs are. My wife's car takes the cheap resistor plugs every 30,000. The high priced plugs don't last much longer. In 300,000 I've tried a few different brands with no luck.

jim

[Brad Johnson]

If the OEMs lasted 85k with no problems, stick with them unless you can find a LEGITIMATE reason to change.  Check the forums for your ride and see what other people's misery has determined.

Brad