1985 FJ60 failed California smog due to high NOx

Joined
Nov 4, 2022
Messages
42
Location
California
Hey everyone, just joined this community today after buying my first Toyota yesterday. Picked up a beater FJ60 and am getting ready to get things in order with it. Previous owner tried smogging it before selling but it failed due to NOx being 202 ppm too high. Smog tech told him its probably a problem with the EGR system. At first looks I see the vacuum system needs to be gone through. Two hoses are plugged with bolts and I see the parts they're supposed to go to. Maybe someone can fill me in on what these parts are before I dig into the manuals. I attached an image of said plugged hoses circled in red and arrows pointing to the two parts in question.

I haven't began to troubleshoot the EGR system yet. I thought I might first ask you guys what you'd suspect the issue might be based on the smog results which I am attaching as well.

The area in California that I reside doesn't require smog tests after the first one when purchasing a car so I don't really need any type of permanent fix, I just need to pass the test once to keep this thing street legal for the rest of it's days. Let me know if you guys have any ideas for me!

IMG_7741.jpg


IMG_7815.jpeg
 
Joined
Nov 4, 2022
Messages
42
Location
California
After looking through some manual diagrams I see one of the parts no longer receiving vacuum is the vacuum switching valve. The other one I have yet to identify. I attached a photo of it.

IMG_7816.jpeg
 

OSS

SILVER Star
Joined
Jun 30, 2017
Messages
4,883
Location
Oblivion
The Toyota emissions manual shows how the EGR system should be hooked up. It also gives tips on how to test it.
High NOx is classic malfunctioning EGR. That’s the whole purpose of EGR— to lower combustion temperature to reduce NOx.

BTW, retarding the timing will lower NOx too, but technically that’s not permitted for a test = fail. That’s why smog techs are supposed to check the timing and there’s a check mark on the test to verify it’s within spec — but many smog techs don’t check (none of mine ever did) and probably don’t care.
 
Joined
May 29, 2007
Messages
3,839
Location
no.california S.F.O BAY AREA (EAST BAY)
Besides the NOx failure, how did he miss the hoses all disconnected? Did you bought it like that? I would start from scratch and go over the entire emission system.
 
Joined
Nov 4, 2022
Messages
42
Location
California
Besides the NOx failure, how did he miss the hoses all disconnected? Did you bought it like that? I would start from scratch and go over the entire emission system.
Excellent question that I have no answer to haha. Yep this is how I got it. I will be replacing the vacuum lines and learning more about the emission system. I was hoping people here would agree with the smog tech that its an EGR issue, seems like that's the case so I'll get to work.
 
Joined
Nov 4, 2022
Messages
42
Location
California
I just went through this, CA Smog - High NOx - https://forum.ih8mud.com/threads/ca-smog-high-nox.1294374/. That thread has a link to a modulator that works if you need a new one. I also pulled all of the vacuum lines from the metal "spaghetti tubing" and used the emissions manual to get each connected to the correct location.
Thanks for the link! what size tubing did you use and how much did you get? Toyota really went insane with the vacuum lines on this thing. I plan on redoing the whole thing ASAP.
 
Joined
Nov 4, 2022
Messages
42
Location
California
Appreciate it!
Just got the new vacuum line in the mail and started replacing everything. Discovered one of the BVSV ports is broken off and the vacuum line to it is capped. I’ll look for a replacement when I finish up but until then which would be the best configuration for this line if I were to run the engine? Should I leave it as is with the metal line capped or does it make more sense to just bypass the valve and make a loop from one metal line to the other. I’m not sure how this circuit works so figured I’d check if someone here has experience with it. Thanks!
 

2mbb

SILVER Star
Joined
Sep 1, 2003
Messages
5,686
Location
WC, CA
Just got the new vacuum line in the mail and started replacing everything. Discovered one of the BVSV ports is broken off and the vacuum line to it is capped. I’ll look for a replacement when I finish up but until then which would be the best configuration for this line if I were to run the engine? Should I leave it as is with the metal line capped or does it make more sense to just bypass the valve and make a loop from one metal line to the other. I’m not sure how this circuit works so figured I’d check if someone here has experience with it. Thanks!
Which BVSV?

The upper one supplies vacuum to the main advance diaphragm for the distibutor. This is functionality (vacuum to the diaphragm) you would need unless you are desmogged (I think).

The lower one is used for the choke opener which opens the choke plate when the engine is hot. Technically you should be able to control the choke plate manually with the choke knob.
 
Joined
Nov 4, 2022
Messages
42
Location
California
S
Which BVSV?

The upper one supplies vacuum to the main advance diaphragm for the distibutor. This is functionality (vacuum to the diaphragm) you would need unless you are desmogged (I think).

The lower one is used for the choke opener which opens the choke plate when the engine is hot. Technically you should be able to control the choke plate manually with the choke knob.
Sorry, meant to post a photo. It’s the lower one. Any advice on if I should loop the vacuum line from one metal vacuum line back to the return or just keep the line hooked up to the port that’s still intact and plug the metal vacuum line that is supposed to go to the port that’s broken? I will order a replacement part later today but just want to fire it up after I finish all the new vacuum lines. Almost finished, just trying to find a more detailed diagram now of the 4 lines to that plug into passenger side of the carb. None of the diagrams I’m finding are detailed enough on that portion.

E3E00DD0-16F3-4EE2-8A38-FDBC0A04CAD2.jpeg
 

2mbb

SILVER Star
Joined
Sep 1, 2003
Messages
5,686
Location
WC, CA
If you close the loop on the vaccum lines then your choke plate will open as soon as the engine starts--not after it heats up. I would leave it disconnected as as your engine heats up, push the choke know in.
 

OSS

SILVER Star
Joined
Jun 30, 2017
Messages
4,883
Location
Oblivion
just trying to find a more detailed diagram now of the 4 lines to that plug into passenger side of the carb.
The emissions manual shows how they’re hooked up.
The spaghetti piping terminates with 4 pipes stacked on top of each other, then there’s 4 short vacuum hoses connected to them and stacked in a little bracket holder.
Then use the diagram shown below to hook them up

BC8F9914-7B0B-4F08-9522-635C862F59E6.jpeg
 
Joined
Nov 4, 2022
Messages
42
Location
California
If you close the loop on the vaccum lines then your choke plate will open as soon as the engine starts--not after it heats up. I would leave it disconnected as as your engine heats up, push the choke know in.
Ok so best to leave it how it is? with the plug on the metal line and with one line going to the port that's still in tact? So that switch basically closes the choke when it detects the engine is warmed up? But pushing the choke knob in will override that switch?
 

2mbb

SILVER Star
Joined
Sep 1, 2003
Messages
5,686
Location
WC, CA
The way it is connected is fine, I think.

The BVSV opens the choke when the engine is warm. The owners manual say's "Never forget to push in the choke button when the engine warms up". The BSBV will override the choke knob being pulled out if you forget to push it in.
 
Joined
Nov 4, 2022
Messages
42
Location
California
EDIT: I couldn't get it started after I finished putting everything back together but realized I had taken out the "engine" fuse from the fuse box when I left town and never put it back in. Started right up once the fuse was put back. Now I guess I'll do a few of the tests from the emissions manual to make sure the EGR system is working before I take it to get smogged. One area I wasn't certain about with the vacuum lines are the ones going from the air box to the check valve/PCV valve/Distributor. Here's a photo of how mine is set up now. I see photos online of people with them connected differently so figured I'd check if any of you know how its supposed to go.

FA70FBC1-4C11-4B98-AA41-D031733CF6BD.jpeg
 
Last edited:
Joined
Nov 4, 2022
Messages
42
Location
California
Also, does anyone know if the part circled in red is a check valve or something else? Thats one of the lines that was plugged/missing on mine so I just ran a straight hose. Wondering if its missing a part.

vacuum.jpg
 

Users who are viewing this thread

Top Bottom