How to Desmog an FJ60

[pdugas]

did you find a donor?

Not yet .

 

[Beehanger]

For me desmog was really more about getting rid of parts that break down and leave the engine inoperable. Most notably is the smog pump. I went through three of them. One, I pulled the broken veins out of and kept going for a while. Another totally seized up and threw the fan belt leaving me stranded. Now I am partially desmogged. Still running the EGR system after extensive repairs. I'd like to remove it all but the reality is that I will need to recurve the dizzy properly and re jet the carb. If you want to do this I suggest using TLC performance/ie JimC. This means down time unless you have a spare dizzy and carb to send him.

If you want to go this partial desmog route realize it does cut back on the cat properly burning off emission gases and your exhaust will be stinky. But its pretty easy. Replace the smog pump with a delete pulley, remove the air rail and air injectors from the head and plug the holes. Remove the air hoses and plug from the air cleaner and valving that went to the smog pump. Later I removed the air valving from the driver's side fender and the cut and welded the exhaust smog piping off the down pipe.

Repairs to my EGR that made it work were: remove and clean the carbon from the EGR valve, replace the egr pipe with a stainless one from SOR. The main reason for this is that the old EGR pipe had badly corroded around the flange and was unable to flush up to the exhaust manifold and maintain a good seal. I replaced the EGR modulator valve with an 80 series that is still available from toyota. You'll know if you EGR modulator is bad if you have "modulation" ...a stupid hesitation in your engine at certain rpms...and you can test the modulator vacuum (follow the emissions FSM instructions). I also had a failed egr VSV and had to buy a generic one and re-design the electrical terminals.

Even with all that done, there is the concern of a failed emission circuit board. So for me the main purpose in desmogging is NOT performance improvement but reliability improvement.

where does the circuit board live? and for that matter, when you desmogged, I know there's some important sensors or fuel cut equipement that needs to be added back on? How does one keep these important sensors that need to be a part of the vehicle still, but were once part of smog equipment? o2 is non esential after desmog with no cat correct?

 

[g-man]

I believe it is behind the drivers' kick panel. Here are some things it controls:

this image from the emission control FSM emissions schematic p.3-3

and here are what those numberd items are:

electrical wires going to the back of your VSVs (vacuum switching valves) and other switches get signal from the board based on things like rpm, cat temperature etc and tell the vsv when to open and close the vacuum signal.

 

[g-man]

There is no O2 sensor on a 2f. Just the cat temp probe.

 

[Gretsch]

where does the circuit board live?

 

[Beehanger]

Not yet .

I believe it is behind the drivers' kick panel. Here are some things it controls:

this image from the emission control FSM emissions schematic p.3-3

View attachment 3346222
and here are what those numberd items are:

View attachment 3346223

electrical wires going to the back of your VSVs (vacuum switching valves) and other switches get signal from the board based on things like rpm, cat temperature etc and tell the vsv when to open and close the vacuum signal.

VSVs are one of the few items NOT deleted, so if this circuit board is malfunctioning then it still needs to be replaced/ have fuses checked?

 

[Beehanger]

VSVs are one of the few items NOT deleted, so if this circuit board is malfunctioning then it still needs to be replaced/ have fuses checked?

I’m running no HAC due to complexity

 

[g-man]

the VSV for the EGR sends vacuum signal to the EGR modulator which controls the EGR. If you delete the EGR there is no reason to keep the modulator or the EGR VSV.

The AI (air injection system) has VSV 1 and 2 ...neither are needed if you are deleting your smog pump and air rail.

 

[g-man]

Search on the "green wire mod". You will want to keep the board unless you are grounding your ICS. Assuming you have a stock carb.

 

[g-man]

Study this diagram and follow all the wires from the board to see where they go. Some are inputs and some are outputs. I believe the cat temp probe, the coil rpms, the vacuum switch, and the speed sensor are inputs. The fuel cut solenoid valve and the outer vent control valve are usually NOT removed on a typical desmog.

 

[Beehanger]

Search on the "green wire mod". You will want to keep the board unless you are grounding your ICS. Assuming you have a stock carb.

non-stock chinese carb... I think i need to keeps ICS with this anyway correct?

PS! I think mine might be toast.... When the rig was running two years ago I would turn on the A/C and, I s*** you not, the rig would start REVVING uncontrollably like a runaway Diesel until i pulled the key.

Any ideas where one can find a replacemnt.

 

[2mbb]

The problem your describe above sounds like your AC idle up speed adjust me screw is set too high (screwed in too far). This is a screw on the front facing side of the carburetor that sets how high the pressure due goes up when the AC is turned on.

 

[pdugas]

The problem your describe above sounds like your AC idle up speed adjust me screw is set too high (screwed in too far). This is a screw on the front facing side of the carburetor that sets how high the pressure due goes up when the AC is turned on.

Not to high jack this thread but what should the rpm’s be with the ac on ?

 

[MoaByte]

Not to high jack this thread but what should the rpm’s be with the ac on ?

800-850 rpm.

 

[g-man]

And the AC amplifier should cut it off at 600-700rpms. There is a blue knob that can adjust this under the glove box.

 

[Beehanger]

And the AC amplifier should cut it off at 600-700rpms. There is a blue knob that can adjust this under the glove box.

View attachment 3348192

so is it 600-700 RPM or 800-850RPM? hahah

 

[Beehanger]

Worked on desmog a lot today. I went with the AGGRESIVE desmog route, no EGR, no HAC, and aftermarket desmogged carb. Care to check my work? Believe Im done. Here's my work so far:

Capped both BCSV's,
Didn't use rightside VSV
Left Side VSV is hooked up as shown in photo (wraps around to front of air cleaner cover)
The ICS is hooked up as shown (WHERES THE "computer" thought??)
charcoal caniseter is gone until I put stock carb back on after desmog.


Let me know what you think,
Dan

 

[g-man]

BVSV's dont need to be plugged. They are solid brass between where they thread into the t-stat housing and the plastic vacuum line ports. They only transmit heat through the plugs that open the valve to allow air to pass through from one line to the other. Its the other side that needs to be plugged ie where they draw vacuum from the intake. If you have removed the metal vacuum line piping just make sure the 3 way air filter on the intake is plugged. You don't have a pcv hose to the intake block off plate below the carb. I see the block off plate but there is a plate designed with a port for the pcv line to attach. What did you do with your pcv vacuum hose? I wonder if the block off plate you used was supposed to be the one that goes to the exhaust manifold where you removed the egr pipe.

 

[Beehanger]

BVSV's dont need to be plugged. They are solid brass between where they thread into the t-stat housing and the plastic vacuum line ports. They only transmit heat through the plugs that open the valve to allow air to pass through from one line to the other. Its the other side that needs to be plugged ie where they draw vacuum from the intake. If you have removed the metal vacuum line piping just make sure the 3 way air filter on the intake is plugged. You don't have a pcv hose to the intake block off plate below the carb. I see the block off plate but there is a plate designed with a port for the pcv line to attach. What did you do with your pcv vacuum hose? I wonder if the block off plate you used was supposed to be the one that goes to the exhaust manifold where you removed the egr pipe.

WIll the truck not run with this blocked? If so ill order it from MANAFRE asap. I bought the set from cruiserparts.net. Assumed I didn't need that pipe b/c their version didnt include that pipe. as for EGR, I blocked the EGR with the other plate they sent me.

 

[Beehanger]

WIll the truck not run with this blocked? If so ill order it from MANAFRE asap. I bought the set from cruiserparts.net. Assumed I didn't need that pipe b/c their version didnt include that pipe. as for EGR, I blocked the EGR with the other plate they sent me.

Does the ICS look right BTW?