Secondary air injection solenoid valve repair,Save $500

Hi everyone, this is my first post,so please excuse me if I screw up. If your a moderator,please move this post to the proper place if I put it in the wrong location. After reading nevenelestsate post on solenoid/manifold removal after having my truck go into "limp" mode I decided to see about repairing the solenoids themselves.I performed this repair 10 days ago and have not had any problems since.With Christmas around the corner,I really didn't have an extra $500 to spend on a replacement solenoid bank and unfortunately,you cant buy replacement solenoids by themselves. So this is basically a follow up to nevenelestate's post(THANK YOU !!) but I'm going into further detail about fixing the seal problem on the solenoids and testing them out to be sure they work. After taking apart the air injection blower/motor assembly and only finding a little bit of dirt with the internal filter being in good shape and not falling apart,I hooked up a couple of small alligator leads to the wires and tested out the blower. No problems,spun up just fine.Next I took apart the solenoid bank/manifold and found a lot of carbon build up on everything.Using a soft wire brush and some rubbing alcohol,I was able to clean all the parts pretty good.It was then that I noticed the melted/deteriorated solenoid seal on bank #1 which had kept the solenoid open and wouldn't allow it to close, throwing out an error code for sure.I pulled out what I could using my fingers and then decided to test the solenoids to make sure they work before going any further. Using my multi-meter I found continuity between pins 1&5 and decided to hook up my test leads to them and briefly test the solenoids by by only energizing the positive side of the leads to my battery.(Please note,I'm not exactly sure if these were the proper two pins for the solenoids as I couldn't find a free wiring diagram for the 2012 Tacoma.There may be some other sensitive circuits in the solenoid heads,so I only energize the circuit really briefly, 1-2 seconds to verify operation).Both solenoids I tested worked absolutely great.Both of these solenoids are spring loaded to keep them in the normally closed position when not being energized during cold start up.I was able to use a small 90 degree O-ring pick to force open the solenoids from inside,wedging open with a small 1/4" hex bit to finish removing the gummy/nasty seal from both sides of the solenoid plunger. After removing the bad seal,I took 320 grit sandpaper folded it over a couple of times and slowly took my time sanding down the mating surfaces to make sure I have a air tight fit.I blew into the inlet and found I had a air tight fit without using the seal at all.The thermal plate( brick red-orange color) is below the solenoids to protect the seals by bending close as the exhaust temps rise,which,in theory, is supposed to protect the seals from the intense heat(haha).I put everything back together,briefly disconnected my battery leads to clear the error codes and my taco started right up,and have not had a problem since. The fact that Toyota engineers have kept this design for many years without improving it really ticks me off. If you test your solenoids and they don't work,find some used ones that do,or shell out $500 +/-.The SOLENOID SEALS are the problem here, at least for me.Why would any engineer put a rubber based seal this close to a major heat source? Oh that's right,it's past the warranty and we can charge $500 for two $30 solenoids. I hope this post of mine helps some folks out.

 

Nice writeup. Welcome to TW

 

Shouldn’t all this be covered under warranty? I thought it was included in the new service bulletin? Good write up though.

 

It’s covered under extended warranty program for 10 years and unlimited miles. They’ll fix it for free.

 

Good job beersludge070 and thanks for the wright-up. I have two questions: Did you replace the rubber seals on the solenoid valves, or just leave them "bare"? How was the seal of the orange seal that is supposed to keep the exhaust from getting to the valves?

 

only the 2012s are covered...

 

They did make changes to these for '13+. There's an air dump that occurs when the engine is shutoff. This dries off the reed valves. Moisture build up on these valves was the cause of failure. '12s did not have this feature