Changing spark plugs

Just did this on my Gen 3 at 12(4)000. The plugs came out pretty easily once all the parts in the way were removed. They looked fine, clean electrode tips, light tan deposits. Brown ring down low on the insulator, as everybody seems to find. Based on how smoothly these came out, I elected not even to bother with antiseize on the new ones.

A couple of my ignitors showed a tiny bit of loose reddish dust up around the top of the rubber boot that goes around the plug. It was easily blown/brushed off. I wonder if it means there's been some arcing there to the metal wall of the plug well.

The new plugs all came out of the box gapped the specified 1.0 to 1.1. mm as nearly as I could measure. They just barely did not pass a 0.043" feeler. I didn't adjust them at all.

Somehow, I ended up with a 14mm spark plug socket that would not grip these plugs at all. It contained a rubber O ring with an inside diameter way bigger than these plugs' insulators. Wished I had @StarCaller's magnetic one. I ended up taking the O ring out, cutting about a 3 ✕10 cm strip of 1/16" rubber and rolling that up to stick up in the socket and let it unroll. That held the plugs well enough to remove the old ones and start the new ones. I took the rubber out for actual loosening and tightening, and just used the socket as a socket. (Was afraid if I pushed the socket all the way on with my rubber inside and it gripped too tightly, I'd never get the socket back out of the plug well.)

The @NutzAboutBolts video was helpful, but I cringed at the end where he puts the wipers back on (puts the arms on pointed the wrong way, starts the nuts, then muscles the arms around to the blades' proper park position). Yikes! Hey, those shafts (and holes in the wiper arms) are (or were) splined—and with very shallow, easily-rounded-off splines, to boot.

A very gentle touch works well here. To start, you can find the handy round dots Toyota printed in the black mask coating of the lower windshield, right where the ends of the parked wipers belong. (Nice touch, Toyota! Never noticed those before this time!) LIne the blade right up with the dot, then lower the mounting hole straight down onto the shaft. (This takes both hands to kind of fight the arm spring so you can really set the mounting hole down flat, not tipped up at an angle by the spring.) By some very gentle back and forth wiggling, you should be able to feel the splines are nicely mated right near that position. Then just hold the attaching end straight down and tighten the nut, without moving anything.

Might be the most delicate operation of the whole procedure....

While changing the plugs ('cause, who'd want to do this work twice?), I also took my first cylinder leakage readings on this car. Cylinders 1, 3, and 4 had excellent results, but 2 was an outlier (still within the 'tolerable' range for variation between cylinders, but just barely). A little disconcerting at 124,000 miles (my old Gen 1 had four well-matched, excellent results when I tested it at 206,000!).

-Chap

 

Hello I'm owner of an Auris hybrid 2010. I finally decided to change my spark plugs at 140 000 miles. What do you think about the state of the spark plugs? Pictures below

 

The coffee color is a good sign. Recommend you enjoy the ride with new plugs now

 

They are overdue for replacement

JeffD

 

So what is the consensus on using anti-seize when changing spark plugs? I know it’s a divided subject on these forums, but what does Toyota itself recommend to its stealership techs?

 

It depends on the spark plugs you buy. Some already have a coating on them, like Bosch.
At least they used too....
But if you only put a little bit on the threads, not a ton, you should be okay.

 

The Toyota Repair Manual makes no mention of lube, so presumably clean/dry threads. Torque thus is 15 lb/ft. If you were to use some sort of anti-seize, I think the concensus is to reduce torque around 25%, say to 12~13 lb/ft. I wouln't "butter" it on, maybe apply thin/even, and wipe with a cloth, leaving a residue.

For Repair Manual info:

Changing spark plugs | PriusChat