Probably quickest to just swap in another one if possible.
AC idle up issue (1 Viewer)
- Thread starter LandoNick
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- Thread starter
- #22
Do you have a part number or source?
No. sorry. But you can temp "borrow" one from your truck, 4x4 vac actuator VSV for example and swap it in to test to make sure it is the VSV causing the problem.
Any VSV that is Open/Close, normally closed, should work fine. The valve is just allowing full manifold vac to the actuator when ON (voltage applied).
The only difference between the VSVs for different models/years (for carb'd Toyota) is usually how it's fastened down and the type of connector.
The little finned-thing that screws into the manifold where the vac hose attaches is not rusted? Broken?
The only difference between the VSVs for different models/years (for carb'd Toyota) is usually how it's fastened down and the type of connector.
The little finned-thing that screws into the manifold where the vac hose attaches is not rusted? Broken?
This is what I used as substitute on mine: (stock on the right)
Spikes substitute would be fine. yours "might" be failing due to heat build up in it's coil after a minute causing it to close again. Purely a guess.
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- Thread starter
- #27
Same electrical connector?
sounds like electric gremlins like mine has too. the 12v to the vsv is getting cut off for some reason.
Here is ac amp thread The A/C Amp Thread
This would be my guess what the problem is.
Here is ac amp thread The A/C Amp Thread
This would be my guess what the problem is.
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for posterity sake...
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OEM Idle Up VSV Replacement Cheap on FleaBay
Just an FYI: This works fine for the NLA (discontinued) A/C Idle Up VSV, and even has the correct connector. OEM Denso. https://www.ebay.com/itm/Denso-VSV-Vacuum-Canister-Purge-Switch-Valve-084600-3550-Mazda-Toyota/233159123857?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
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- Thread starter
- #31
Love it thanks!for posterity sake...
OEM Idle Up VSV Replacement Cheap on FleaBay
Just an FYI: This works fine for the NLA (discontinued) A/C Idle Up VSV, and even has the correct connector. OEM Denso. https://www.ebay.com/itm/Denso-VSV-Vacuum-Canister-Purge-Switch-Valve-084600-3550-Mazda-Toyota/233159123857?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
- Thread starter
- #32
So tested the connection to the VSV. Hooked it up to a meter. When the ac button is pressed I have 12volts. Then after the minute of running voltage is gone. What would be cutting that source off? The ac clutch is still engaged. I thought maybe the vacuum diaphragm on the idol up circuit was cutting off but it’s 12 volt source. Not sure where to go from here.
I believe voltage to AC Idle up VSV is controlled by AC Amplifier. I think thru ground
- Thread starter
- #34
Check voltage at the amplifier harness?
The A/C Amp Thread
This thread is all about FJ60/FJ62 A/C amplifiers. You know, that little black box that mounts on the evaporator case behind the glove box. There are plenty of other threads concerning A/C amps and I thought about adding to those, but in the end decided that the information here breaks enough...
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I also have to ask, you realize the AC Idle up cycles On/Off with the Compressor clutch engaging ?
apart from tweaking the trimpots [probably won't help] on the amplifier, a new amplifier might be needed. Unless you see something obviously burn't out on the amp circuit. Look closely for bad solder joints...... you might be able to repair it yourself?
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- Thread starter
- #37
when the idle up circuit is on I’m at 1,000 rpm. I assume that is for the extra work the engine has to do with the compressor on. So when the high idle shuts off. The compressor is still engaged and the truck will be below idle at say 450-500. Which it seems like it a struggling. If that’s normal then great it just doesn’t seem like that is right. But who am I to question Mr Toyota.The A/C Amp Thread
This thread is all about FJ60/FJ62 A/C amplifiers. You know, that little black box that mounts on the evaporator case behind the glove box. There are plenty of other threads concerning A/C amps and I thought about adding to those, but in the end decided that the information here breaks enough...
I also have to ask, you realize the AC Idle up cycles On/Off with the Compressor clutch engaging ?
From the chassis and body manual:
The amplifier controls both the VSV to the AC Idle up circuit and the compressor engagement. Normally the AC will cycle on and off based on the temperature in the evaporator. You can try adjusting the knob on the amplifier, or source a replacement amplifier.
There isn't much other information how the system works, but from this description it seems the amplifier cycles the VSV on and off and the compressor disengages based on engine RPM.
The amplifier controls both the VSV to the AC Idle up circuit and the compressor engagement. Normally the AC will cycle on and off based on the temperature in the evaporator. You can try adjusting the knob on the amplifier, or source a replacement amplifier.
There isn't much other information how the system works, but from this description it seems the amplifier cycles the VSV on and off and the compressor disengages based on engine RPM.
- Thread starter
- #39
Do if i have the ac on and at 700 rpm the clutch should turn off? Then the idle should go up to 1000 RPM?
I think the point is, if the RPM falls below the limit set by the knob on the amplifier, then the amplifier should turn the compressor off. Since the RPM is getting too low, and the compressor is still engaged, I think it is easy to adjust the knob to see if anything changes.
Somehow there are multiple circuits from the amplifier that control the compressor clutch. The amp must turn on both the VSV and engage the clutch at the same time. It must also turn off the VSV and (maybe) the clutch during normal cycling, but there is also the RPM is monitored to turn off the clutch.
Otherwise, I would have to agree with posts above that the amplifier may not be working properly. By checking voltage applied to the compressor clutch and the VSV you might be able to confirm that.
Good Luck
Somehow there are multiple circuits from the amplifier that control the compressor clutch. The amp must turn on both the VSV and engage the clutch at the same time. It must also turn off the VSV and (maybe) the clutch during normal cycling, but there is also the RPM is monitored to turn off the clutch.
Otherwise, I would have to agree with posts above that the amplifier may not be working properly. By checking voltage applied to the compressor clutch and the VSV you might be able to confirm that.
Good Luck
