o2 sensor vs. smog check vs. CEL (also looking for someone who owns a 1st gen near Ontario, CA)

I recently purchased a 1st gen (3.4 4x4 w/ E-locker) from a friend's dad. It had been in an accident (front end) and had sat for roughly 6 months. Upon purchase I bought a new battery as the old one was done-zo. Went to get it smoked, and the guy said put some more miles on it, as the sensors haven't been accounted for in the ECU. I drove it about 30 miles, and took it back. He said drive it more, orrrr, buy a new rear o2 sensor. But, here is my question... I have had to replace an o2 in the past, but I knew so because a CEL came on. Is it possible for the sensor to be no bueno, but not throw an CEL? or should I keep driving it in the hopes that the sensor just need to be registered?

ALSO, this truck is a little strange. It has a Clutch Start Cancel button, but it's an auto (my 5spd T4R has that button, so I am aware of what it does). Also, it's missing the cruise control module. I suspect a few other things are weird. Anyone else with a 3.4 nearby that would let me poke around for about 15 minutes so I can see whats missing/wrong on this truck? I would be super grateful.

Thank you!

 

Your truck is an automatic... and has a clutch start cancel button? What even...

Can you trace where the switch goes?

 

Right? It is connected to something, as there is a pigtail running out of it behind the dash. I plan on following the wiring sometime soon, I just have a list of other things to get to first!

 

Make an account with Toyota here and plug in your VIN. Toyota will report what it came with from the factory and all service records done at a Toyota dealership.

 

Thanks you for the suggestion. I've been a toyota guy for quite some time, so one of the first things I did was look it up. I have my 80 series, my other two Tacomas, and the 4runner on there. It is a great resource. But it definitely came as an auto, and it definitely came with CC. I think someone got a little liberal with the wcrecutters, 10mm wrench, and the parts bin.

 

Send this guy your VIN:

https://www.tacomaworld.com/threads/free-autocheck-running-carfax.466088/

I got a report for two of my cars from him: it reports just as much as a CarFax. Told me the mileage on my truck from the state record when it got Smogged and a bunch of other stuff including when it was used and registered as a fleet vehicle. Even brings up police records (that I didn't know existed) on my E320

 

Awesome! Thank you. Now, how about that o2 sensor?

 

There's a way to test an O2 sensor, something with a multimeter and resistance but I don't know the exact procedure

 

The way of testing the o2 sensor isn't purely bible, my snap on scan tool thought mine was bad and was out of voltage range. You can test with a heat gun but that's a part that can go bad fairly easy and test out ok anyway. I have three good ones used all factory purchased PM me and I'll see what I can do. Do you have three cats or one? You might have afr sensor which is different. Are we talking pre cat sensor or after? I'll help ya. I'm not too far from Ontario.

 

I believe I have one cat (truck is parked at a family member's house since it is still non-op, pending the smog test). This is the downstream sensor the runs from under the cab to under the seat. Thanks for any and all help. I appreciate it.

 

Hey PJ i work in ontario ca off the 15 fw man . I have a v6 .

 

Good news for you and bad news for you! that downstream sensor doesn't go bad, but it tells you it's bad when the cat goes out code p420. I know I know not that 420 lol, but you're cat is more than likely bad!,get under the truck bang on it with your hand if it rattles replace, if it's sounding solid you can possibly burn it clean. If you showed a p420 code on a scan tool it's cat related don't put in an o2. A factory cat for your truck (federal addition) is 1000+ clams, don't waste that kind of cash; look into walker cats and know that fed law states that all replacement cats must last 5 years. Please pull codes for me and I will happily help you get past this! Once you fix it you'll love it, obviously you've had many yotas as have I. Good luck!