Every time you allow unknown quality parts into your vehicle you potentially bring in a chain reaction of problems, that can pollute any further diagnosis or repairs.
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I think if I was in your position I would add some Chevron Techron and leave well enough alone. If you choose another route then be prepared for frustration.
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If you decide to remove and recondition the originals, then replace any relevant seals at the same time, preferably with originals, or original equipment manufacturer from Rock Auto.
Remember you bought the best vehicle and it has served you well. It's not the time to allow any unknown quality parts into that system.
As a diagnostician I liked to keep potential consequences to a minimum, it's almost impossible to figure out what is going on when you can NOT trust your repair processes to actually be finished. No matter how good you are, you are only as good as the poorest quality part you buy.

My 2000 and 1998 Toyotas both run perfectly with the original injectors and Techron occasionally and get superb fuel mileage (46 average and 23 average). They run as well as they did new. I even have a spare engine for the ECHO and can have those injectors cleaned if necessary, but the Techron does the same without any disassembly. Many times I have heard from people and my customers about problems that arose when repair processes were done.

 

Every time you allow unknown quality parts into your vehicle you potentially bring in a chain reaction of problems, that can pollute any further diagnosis or repairs.
___
I think if I was in your position I would add some Chevron Techron and leave well enough alone. If you choose another route then be prepared for frustration.
___
If you decide to remove and recondition the originals, then replace any relevant seals at the same time, preferably with originals, or original equipment manufacturer from Rock Auto.
Remember you bought the best vehicle and it has served you well. It's not the time to allow any unknown quality parts into that system.
As a diagnostician I liked to keep potential consequences to a minimum, it's almost impossible to figure out what is going on when you can NOT trust your repair processes to actually be finished. No matter how good you are, you are only as good as the poorest quality part you buy.

My 2000 and 1998 Toyotas both run perfectly with the original injectors and Techron occasionally and get superb fuel mileage (46 average and 23 average). They run as well as they did new. I even have a spare engine for the ECHO and can have those injectors cleaned if necessary, but the Techron does the same without any disassembly. Many times I have heard from people and my customers about problems that arose when repair processes were done.

I bought the Techron today and am back to my OEM mantra. I should know after 4 years of almost no clutch after it was replaced by a local garage. They did a clutch kit, master and slave. It never worked right after. It didn't release freely. Even with the pedal mashing the floorboard it was hard to shift, barely drivable. I took it back several times and they would just bleed it and say it's an old truck. It was when started the reno and decided to replaced the 4-year-new aftermarket master cylinder with a Denso OEM. Like magic, the clutch was back.

Also, my fuel system has been kind to the injectors. When I replaced the pump bracket the tank was startlingly clean. I was expecting a 30 yr old mess after all the YouTube how-to clean your tank videos. Not a trace of sediment or goop. Just clean shiny metal that you would think was 2 years old. I was amazed. I have a video of it if anyone's interested. So, I'll run the Techron and call it good for now. Besides, I'll pull the intake manifold off a lot quicker next time. Thanks for the helpful feedback.

 

My 1998 RAV4 last fill-up 25.179-MPG. My "I'm original Owner" 1991 Toyota XtraCab Deluxe pickup last fill-up 20.4538-MPG. I wouldn't mess mess w/ your Fuel Injectors.
1/ I endorse Chevron Techron (or any reliable product w/ PEA). NOTE: both my mileages are mixed CITY/HIGHWAY.
2/ I ONLY install 100% Pure Gas ("Marine Gas", "0% Ethanol") in both my Toyotas. Engines weren't designed to eat CORN. When I started this practice, both Toyotas experienced better miles-per-gallon.

 

Fabulous, enjoy the great decision you made a long time ago that gives you a vehicle with another 50% of it's life expectancy left. By that time I'll be 86 and probably not capable of pushing in a clutch pedal, but you never know!