Replace plugs and other Maintenance after 100K+

At 100,000 miles your spark plugs original Toyota SK16s or whatever's in the car should be something similar are just now worn out so there you go It is pretty easy to change spark plugs even if you have to remove the wiper tray in your model It's like two or three fourteens and the rest tens little electric screwdriver with a 10 mm on the end of it whips all those out like instantaneously unplug the wiper mechanism and set it all on the floor and there you go while you have that out you want to be looking around behind your engine at the head gasket and the valve cover and the timing chain tensioner and the oil pressure sending unit any of those things are leakers so you want to address that while you have it apart or you'll become very good at whipping out the wiper tray. But other than that there's no reason in this world that you can't do this in your driveway I do it all the time It is very boring easy work you just have to be there standing. That's what you're paying the mechanic for being there and standing up and having some tools so if you can do the same thing you can save whatever that hourly rate you're talking about is tada.

 

There isn’t much to do at 100k, refer to your maintenance schedule and ignore the dealer

 

Where’s “Riverside”, in California, USA? (Google Maps is showing me ten Riversides, in various States)

Toyota USA recommends 120k miles or 12 years (whichever comes first) for plugs, no service interval for the ignition coils. In California it’s somewhat inexplicably longer, maybe 150k miles or 15 years?

Read the Toyota USA publication Warranty and Maintenance Booklet; it’s all outlined there, albeit in a mind-numbing event-by-event format. If that’s misplaced, you can download a pdf version at Toyota Tech Info.

“My service center” is a Toyota dealership? They tend to do their utmost to downplay any mention of the aforementioned publication.

The plugs in the pic you posted are recommended by that service centre? Those are not the plugs specd in Owners Manual. If that publication is missing, again: Toyota Tech Info has a pdf version.

look into EGR cleaning too, see first two links in my signature (on a phone turn it landscape to see signatures).

 

100k miles or 10 years is the engine coolant change. “Fuller” brake inspection is every 30k miles or 3 years, may have been overlooked?

 

I’m doing separate posts cus I’m tired of PriusChat’s $@%#! propensity to overwrite previous edits when doing yet another edit. It bit me good on my first post.

 

I can’t see replacing plugs by time instead of miles, and now we have a (supposed) recommendation from Tampa hybrids not to replace coolant?

 

The OEM iridium plugs are pretty stout. I pulled out the ones on my old Prius C @ 80K miles for inspection and put anti-seize on the threads and electrolytic grease on the spark plug boot. No decernable wear or issues. On older plugs, you could usually see the edges of the electrodes burning / rounding off, - I found none of that on those 80K miles plugs. I'd be more than comfortable going another 40K-70K miles on them. No OEM change interval for the coils or boots - just lube the boot so they don't stick to the plug.
IMHO; Changing know good OEM parts with questionable and possible counterfeit parts is a gamble. You won't get the reliability of a genuine OEM unit. I'm mainly alluding to the Duralast product you have above. I've never had issues with genuine NGK products. The Nippion-Denso stuff, 40 years ago, was junk. Now they're excellent.

@Mendel Leisk; we get to go the extra 50K miles in Ca; because of the magnetic field that surrounds our state..
It's probably a Cal-EPA thing.....