I started this thread kinda in the middle of my story.
I went in under the intake to do some pre-emptive maintenance to the secondary air pump crap. Why it's under the intake is not a question I have answers for, other than dumb design.
The air pump has a small mower-like sponge filter in it, which has been a nightmare for Tundra's with 2UZ-FE. The more that pump runs (cold engines in colder climates) the more that little filter gets sucked into the blower motor (fused with 50A) and clogs up the valves that feed that air into exhaust, which is supposed to help heat the cats faster. When the related DTC's are logged the owner has to pay near $3000 to have a dealer fix it. OEM parts are about $800. I removed the little sponge filter and attached a K&N-like clamp-on air filter to the inlet snout of the fan assembly (a common thing to do).
So, my little filter was still there, but signs/evidence the fan blades were starting to suck it in. I also inspected the motor itself, and no sheet, they wrapped one lead wire around the body and over the other wire before exiting the assembly. No sheeting, the two wires were chaffing each other and the pos had visible copper. So I had to fix that about-to-happen problem.
In prep for doing that work I got some 'new' injectors and new plugs. Figured then was the time to do it.
All that work went ok, then the no-start issue. I did some initial testing in the relay box and the C/OPN relay did not work as "I" expected it to, but in fact it was working as designed. I then came looking for some answers as to why what I was seeing did not make sense...... hence my initial post. Along the way I did learn for safety reasons the C/OPN relay will not engage w/o a signal from crank sensor, or if an airbag is deployed. This is ECU functionality/info that is not well known by many. I had even talked to my dealer service manager guy, who told me the fuel pump turns on as soon as the key gets to run/on position, which is just bs. The ECM will only start the pump during starting cycle, and stick it on when ECM detects a running engine.
So, that's the long story of it.
Miller time
