05 Tacoma 4 cyl secondary air injection system

My 05 (101,000 miles) was making a whine on startup. Then after a couple of weeks the check engine lite came on. Local garage wanted $1300. to replace.
I read on this forum about the system.
I removed the pump - filter was gone, 40% impellers ground down, but I think pump still works.
Local garage said valve was stuck open.
I am trying to take off the valve, and see if I can clean and see if it still works.
Slowed up by wrestling with a rusty nut - fortunately Taco not my prime transportation.

I have several questions:
1) if the valve and pump still work and I re-install (with new filter on outside of pump), will the 05 Taco go into limp mode?
2) I read where at least one 05 Taco owner put a electrical bypass on. He posted back in 2016. My question is does it still work?
3) is there some danger to driving with check engine lite on if pump/valve quit working?
4) I see aftermarket pump and valves for sale - are they worth the money?

anything I forgot to ask?

Thanks.

 

There is a ton of information on the SAS but not a lot of continuity. I can't see any posts about aftermarket air pumps. Reed valves seem to mostly be OEM. I don't see those offered aftermarket unless they are used. This seems to be a fairly complicated system and it can sometimes be difficult to troubleshoot.

I was going to by a really nice 2008 2.7 Taco but after reading these posts I am reconsidering because I just got whacked with the dreaded p0442 evap code on my Landcruiser! One thing at a time please. There is truth that car electronics saved the ICE, but they simply don't age well. Might be time to buy a "new" car, meaning one that is 2-5 years old instead of 15-20years old , like everything in my fleet!