Northern Virginia Roll Call

P0420. It’s been on ever since I’ve owned the truck. Replaced my downstream o2 sensor few years ago and no change. I can always monitor and clear it with my ScanGauge though, so I’m hoping if I clear it before having it tested I could be good? I’m definitely nervous about this.
Also yes, my cat is installed

 

Probably won't work. The truck also has to pass readiness for the test. Once it passes readiness the light will probably come back on.

 

Do you have any go-to places in mind?

 

No. They're all pretty much the same. They hook up to your OBD II port and check for readiness, hard and soft codes. They're also supposed to do a visual check of emissions equipment. That part doesn't always happen.

 

They won't do emissions if the system says you don't need it so if you can manage to drive by one of the mobile screeners they put on offramps

 

You can try this, but I think you have to do it twice in two weeks.

 

Did you have an emissions test in your previous state of registration?

 

I briefly read into that. I see there’s one in Chantilly on 28 near Sully Rd... I’d much rather do that. But how do I get the results from it?

 

You don't. It's automated-ish.

 

I’m from VB, and I see you’re from Hampton Roads area too. So I’ve never done it before moving up here

 

Gotcha, nevermind then. That was one of the exemptions so I was curious to buy you some time to figure it out. No dice though. Could just try and Keep it registered down here.

 

If you've got no other codes replace the other O2 sensor. If that doesn't fix it then the cat. Rock Auto is your friend.

 

Thing is, I moved up here last spring but I wasn’t required to do emissions before my registration went out in July. So idk why now all of a sudden I have to do it.

 

There's sort of a workaround kind of like Randy was saying. You don't need to change your registration back to the Hampton Roads area, but you can say the vehicle is garaged there. They only ask for the county and no proof.

 

P0420 is downstream O2 or a bad catalyst 99% of the time. 95% of the time it's a slow-switching O2 sensor.

I'm fairly certain bank 1 is passenger on the 4.0L and driver on the 4.7L (assuming this is the T4R) so make sure you did the right downstream sensor. A lot of people assume its always driver and do the wrong one when it's not.

edit: Just realized 2001 was still the third gen 3.4L I think... passenger side on that one.

 

Well somehow Manassas Park got ahold of my info and made me register it with the city. So I have that silly red decal in my window. As much as all of these options sound perfect, I feel like I’m gonna get screwed on this one. But hey who knows. Hopefully it’ll pass and none of this will even matter. I’m gonna aim for getting it done either tomorrow or Friday.

 

I’ve got an ‘01. I just hope it’ll pass and then none of this will even matter. But I have a certain gut feeling about this. And yep it was passenger side that I replaced a few years back. Used OEM, too

 

Yeah realized that and edited because it didn't click that was still best gen 4Runner. Trying to remember and I think there's two under there but that might have been a CA thing. If it's just the one it's probably a universal part any exhaust shop could weld on to get you to pass.

 

emissions is every other year

 

No never saw that thread. But a guy in the 50+ thread that is a 45 year master toyota mechanic told me it's an evap check that the truck performs 6 hrs after shutdown. So his advice is to not tap into anything engine related. So I'm gonna run the wire inside to the other fuse block tomorrow at work. I've never noticed any sounds of any pumps running when it does the check tho.