I’ve owned this car about six years. I put about 35,000 miles a year on it. For some reason about two years ago, a phenomenon started where the windshield washer check valves only last about six months. I just buy them off Amazon. You can get two of them for several dollars. Places like Advance Auto sell the Dorman brand for $24.97 and they state “limited lifetime guarantee “, which would probably be a better choice if you could just walk in and get one, but sometimes they don’t have them in stock either so I just figured why not buy them off on Amazon. Also I guess you could get them directly from Toyota, but I don’t live near a shop. Is it possible on this tiny plastic part that the better brands are just that much more robust or could something else be going on? It appears to be a closed system, no degree getting in the tank or anything.
FWIW I would offer something else is going on. For 4 of your 6 years of ownership, there were no issues. Not mentioned is the exact failure/ issue of the valve. What changed? Brand of w/s fluid perhaps? In my experience, I have seen some brands of fluid coagulate and gum up lines and valves. So, try to flush the system with hot water then use GM (General Motors) Opti-Kleen concentrate mixed in the ratio with distilled water. That's my 2 cent comment... good luck.
otoh, the oems only lasted 8 years, which seems unusual. not sure i've ever heard of anyone having to replace them.
They are getting severely clogged. I do use a winter blend , whatever is the best you can buy off the shelf at the time… during winter. And usually the premium bug cutting stuff during summer. Now that I think of it, I usually use the best stuff available off the shelf I thought about mixing it, I just don’t like the separate need for distilled water. There’s a good brand I think I saw at Napa, 2010 I think it is. iPhone ?
Have you thought of pulling out the windshield washer reservoir, pump and screen? Cleaning the gunk out of it? It sound like your not using distilled water, if your filling with 'hard' water, there could be mineral buildup causing things to jam up - kinda like toilet bowl rings. If the check valve is getting clogged or jammed up; could there be contaminates being pumped into it causing the valve to jam up? Clean everything out, blow out the lines, use distilled water from now on or clean windshield fluid. Do not mix different brands of fluid, you can get a chemical reaction and a precipitation that clogs your system. Replacing the same part over and over again - not fixing the underlying problem is the very definition of insanity.... Hope this helps........
i've only ever used the cheapest premix from home depot. never had any problems, but there's no bug cutter in it.
The rear washer port and the front washer ports have two different pumps. If there’s crud in the bottom of the tank, wouldn’t one think it would clog up the rear also? I’m going to assume the ones on Amazon are cheap and inferior to OEM or even Dorman. iPhone ?
The rear motor sits higher than the one for the front. Because the front is used more. So it leaves a lot more fluid so it doesn't run dry. I read somewhere decades ago it's "about" 50%. So when that starts to run dry, the rear won't work and you'll know to fill it. Because it's rare that anyone checks the washer tank.... The solvent itself will eventually clog things up because it dries in the lines, and clogs the nozzles.... The resivior will get slimy and needs to be washed out with water.
Mine failed at around 35k 8+ years ago. I bought a replacement on eBay, it was defective, so I just went with a straight tube, haven't had a problem since I also make my own washer fluid, very cheap and very effective. One gallon jug, fill with tap water, add 1-3 teaspoons of dish soap (I prefer the blue Dawn), or whatever a good squirt is. You can mix around for strength levels, stronger cleans better, but leaves some film. Either way you're making a gallon of superior windshield cleaner for less than 5 cents USD. I've had a couple cars with clogged squirt nozzles become unclogged with the use of the dish soap mix.
You mean the problem where you only get fluid to squirt on one side of the windshield and not the other, and you have to replace that little 1:2 valve? Cause that stupid thing has failed for me twice.