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Can anyone tell me what this is/does? It has electrical connection and looks like 2 vacuum ports. Any ideas?
96786
 

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It's what's known as a VSV or Vacuum Switching Valve, also known as a solenoid valve - they come in two styles, two port and three port - some three port ones will have a breather cap on one of the ports making it look like a two port. When power is applies to the electrical connection a plunger moves in the valve body and "switches" the vacuum ports - if it's two port it will change from open to close or vice versa, if is's a three port, one port is switched to connect to one of the other two, and when power is applied it connects to the remaining one.

VSVs are used for multiple tasks involving vacuum or airflow - EVAP canister purge valve is one, EGR control is another, on carburetted engines they may be used to control "idle up" mechanisms, and on some 4WDs they are used to engage/disengage free wheel hubs.
 

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Thanks so much for the response. Is this something I should be concerned with not being connected. I just bought the car and going through everything. It runs great but failed emissions for high CO. Can this cause that?
 

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Thanks so much for the response. Is this something I should be concerned with not being connected. I just bought the car and going through everything. It runs great but failed emissions for high CO. Can this cause that?
Take a second picture of it, with your hand out of the picture so we can see it properly - depending on what it should be connected to, it could be the cause of an emissions failure, I'm thinking more high NOx than CO, but, as I said, it depends on what it should be connected to and/or what has been bypassed or left disconnected.

Ack's FAQ Samurai SJ-413 Carburetor Vacuum Line Maintenance

Based on the details in the link provided above, that seems to be an "idle-up" actuator control, and if that's correct, then no, it won't impact CO emissions - idle up mechanisms are used to "bump" the idle speed slightly to allow the engine to cope with slightly higher loads, for example, when electrical loads (lights, blower fan, etc.) are switched on, or, if the vehicle has it, power steering and/or air conditioner.

At a glance the picture appears to show a three way VSV, and most idle up valves are two way.
 

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Discussion Starter #7
Take a second picture of it, with your hand out of the picture so we can see it properly - depending on what it should be connected to, it could be the cause of an emissions failure, I'm thinking more high NOx than CO, but, as I said, it depends on what it should be connected to and/or what has been bypassed or left disconnected.

Ack's FAQ Samurai SJ-413 Carburetor Vacuum Line Maintenance

Based on the details in the link provided above, that seems to be an "idle-up" actuator control, and if that's correct, then no, it won't impact CO emissions - idle up mechanisms are used to "bump" the idle speed slightly to allow the engine to cope with slightly higher loads, for example, when electrical loads (lights, blower fan, etc.) are switched on, or, if the vehicle has it, power steering and/or air conditioner.

At a glance the picture appears to show a three way VSV, and most idle up valves are two way.
96793

96794


I assume this is the connector. It fits and there are two but the other one doesn't reach it.
96795


Wire Colors
96796


Dangling vacuum hoses. One reaches and is the right size, the other doesn't reach but may be broken.
96797


This is where the dangling vacuum hoses are connected on the other end.
96798

Thanks again for your help!
 

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Discussion Starter #10
Take a second picture of it, with your hand out of the picture so we can see it properly - depending on what it should be connected to, it could be the cause of an emissions failure, I'm thinking more high NOx than CO, but, as I said, it depends on what it should be connected to and/or what has been bypassed or left disconnected.

Ack's FAQ Samurai SJ-413 Carburetor Vacuum Line Maintenance

Based on the details in the link provided above, that seems to be an "idle-up" actuator control, and if that's correct, then no, it won't impact CO emissions - idle up mechanisms are used to "bump" the idle speed slightly to allow the engine to cope with slightly higher loads, for example, when electrical loads (lights, blower fan, etc.) are switched on, or, if the vehicle has it, power steering and/or air conditioner.

At a glance the picture appears to show a three way VSV, and most idle up valves are two way.
Looking at the link you sent, it does look like the VSV. It's just installed upside down. Also, I don't have a stock carburetor, it is a Weber.
 

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Discussion Starter #11
It's what's known as a VSV or Vacuum Switching Valve, also known as a solenoid valve - they come in two styles, two port and three port - some three port ones will have a breather cap on one of the ports making it look like a two port. When power is applies to the electrical connection a plunger moves in the valve body and "switches" the vacuum ports - if it's two port it will change from open to close or vice versa, if is's a three port, one port is switched to connect to one of the other two, and when power is applied it connects to the remaining one.

VSVs are used for multiple tasks involving vacuum or airflow - EVAP canister purge valve is one, EGR control is another, on carburetted engines they may be used to control "idle up" mechanisms, and on some 4WDs they are used to engage/disengage free wheel hubs.
I also found an open vacuum port on the bottom of the EGR valve that was just sucking air. I put a cap on it and it slowed the idle down, but still runs fine. Could that also contribute to the emissions issue?
 

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I also found an open vacuum port on the bottom of the EGR valve that was just sucking air. I put a cap on it and it slowed the idle down, but still runs fine. Could that also contribute to the emissions issue?
Yes..,,egr will affect emissions
 

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I think you can forget about ever passing emissions again - not without refitting an OEM Hitachi carb and all the missing emissions paraphernalia.
 

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View attachment 96798
Thanks again for your help!
This is a different style of VSV, and this one is for the EGR modulator, so the first one is for the idle up VSV - but as I mentioned none of it is going to matter any more, not with the weber installed.

Curiosity question - does it still have an oxygen sensor fitted in the exhaust manifold and is it connected?

The OEM carburetor is an electronic feedback Hitachi, sort of a precursor to throttle body fuel injection, with a very primitive ECU that would be required to control the mixture (lean/rich) and also the rest of the emission equipment, right now the high CO is going to be a function of the carburetor jetting - you may need to look for ways to "bypass" the emissions testing requirements.
 

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Discussion Starter #16
This is a different style of VSV, and this one is for the EGR modulator, so the first one is for the idle up VSV - but as I mentioned none of it is going to matter any more, not with the weber installed.

Curiosity question - does it still have an oxygen sensor fitted in the exhaust manifold and is it connected?

The OEM carburetor is an electronic feedback Hitachi, sort of a precursor to throttle body fuel injection, with a very primitive ECU that would be required to control the mixture (lean/rich) and also the rest of the emission equipment, right now the high CO is going to be a function of the carburetor jetting - you may need to look for ways to "bypass" the emissions testing requirements.
Yes, it does have the O2 sensor. Just replaced it actually hoping it will help pass. It is actually barely failing, I was suprised.
 

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I know the EGR will affect emissions but I was looking for this particular port being open could cause high CO reading.
I'm surprised it's even close to passing with a Weber fitted. Which port did you block on the EGR?
 

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Yes, it does have the O2 sensor. Just replaced it actually hoping it will help pass. It is actually barely failing, I was suprised.
I know the EGR will affect emissions but I was looking for this particular port being open could cause high CO reading.
What I'm trying to get you to understand is none of this matters anymore - the Hitachi carb is gone, the ECM that managed it may or may not still be there, but, even if it is, there is no way for it to control anything, because the carb is gone.

The Weber carb is an "old school" carburetor, it doesn't know that there is an O2 sensor fitted, it doesn't know what EGR is, all it knows about is airflow through the venturi, it will "meter" fuel based on that air flow - if CO is too high, it'll be because a jet (one of several) is too large, or the wrong emulsion tube has been selected.
 
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