I will try increasing it. thanks I now see the link in the diagram posted.
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How to install A/C in a 1st Gen Pickup/4Runner (3 Viewers)
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The knob on the amplifier adjusts the RPM point it kicks in. The knob on the idle up valve on the intake adjusts idle speed when the A/C is on as Pappy said.
I have an A/C amplifier I'm not using from an 86 if anyone needs one. I may have two for an 86 and possibly one for an 88.
I have an A/C amplifier I'm not using from an 86 if anyone needs one. I may have two for an 86 and possibly one for an 88.
How come nobody has posted the PIO ( port installed option ) dealer installed A/C technician installation booklet / installer step by step genuine NipponDenso instructions….?
( English language format of course ) ….
( English language format of course ) ….
So I turned it to high and I should have turned it to for earlier idle up?
The adjustment on the A/C amplifier under the dash basically adjusts at what RPM the A/C clutch engages.
For example, If your idle is set at 750 RPM and you turn your A/C on and it doesn't kick in, turn the knob a bit until it does.
The knob on the valve on the intake controls the idle RPM AFTER the clutch engages (A/C on). So the engine doesn't lug with the load from the compressor. It compensates.
For example, If your idle is set at 750 RPM and you turn your A/C on and it doesn't kick in, turn the knob a bit until it does.
The knob on the valve on the intake controls the idle RPM AFTER the clutch engages (A/C on). So the engine doesn't lug with the load from the compressor. It compensates.
The low pressure switch prevents the clutch from engaging if you lost refrigerant to protect the compressor.
The knob on the A/C amplifier will not override that.
The knob on the A/C amplifier will not override that.
I have a fully functioning AC system( proper charge) sometimes and every time I jump the power wire to the compressor clutch. Other than a stuck VSV I'm not sure what is causing my sometimes it works. Looking for a replacement VSV for my '85 system now.
So I'm still trying to trouble shoot my system . When I accelerate go past 1000 rpm the clutch kicks on. But when I let go of the gas sometimes the clutch stays on some times it does not. So at idle it doesn't always engage. I was wondering if this could be due to too much r134 or too low r134. I have the gauge that the refrigerator bottle came with , is that a bad way to gauge the refrige in the system do I need to borrow some proper gauges to test how much is actually in there and then test? When I accelerate the clutch kicks on without fail and blows cold. Do I need to adjust the knob on the core box? Any help would be great. What is the proper level for a r134 conversion?
If it comes on and cools well you are probably not low on refrigerant. Gauges will confirm that though. If the low side drops enough as it cools, maybe it is cycling off?
If you can directly power the clutch and it cools like it should, the clutch is not the problem.
If the clutch only engages above 1000 RPM, it sounds like the knob on the A/C amplifier needs to be adjusted. What I would try first if it was me. At idle, turn on the A/C and turn the knob and see if the clutch will engage. It usually only needs a little bit of a turn in my experience.
If adjusting it works, THEN you turn the knob on the idle up valve on the intake to set your idle speed.
If it still doesn't kick on after adjusting the knob on the amplifier, it's bad or something is probably wired wrong. Assuming you ruled out the clutch by directly wiring it.
As far as how much to charge it, IDK what "volume" is specified. I typically charge using gauges as a guide but I also put a thermometer in one of my vents and stop when it gets the coldest. My personal experience after converting entire company fleets of vehicles from R12 "back in the day" is that they cooled best slightly under the recommended charge from the conversion guide manual that was supplied back then. I had a charging station that could add or subtract refrigerant by 1/10 of a pound and we monitored the temp coming out of the vents. It would get colder up to a point and then start going back up. At that point we pulled a little back out to where it was coldest.
As far as how much refrigerant on these trucks........I don't think I've ever used an entire can of R134 in any of mine. I'm talking the ones Walmart sells. 11 or 12oz cans I think. I probably use most of what is in that size can. There's usually a little left.
Pressures depend on temperature and where you live matters. I'm in AZ and even when it's 110 or higher out here I think my high side gets to around 200 PSI when I'm charging. I don't remember what pressure the compressor vent valve blows off at but it will pop off if you go too high.
Sounds like you're making progress.
If you can directly power the clutch and it cools like it should, the clutch is not the problem.
If the clutch only engages above 1000 RPM, it sounds like the knob on the A/C amplifier needs to be adjusted. What I would try first if it was me. At idle, turn on the A/C and turn the knob and see if the clutch will engage. It usually only needs a little bit of a turn in my experience.
If adjusting it works, THEN you turn the knob on the idle up valve on the intake to set your idle speed.
If it still doesn't kick on after adjusting the knob on the amplifier, it's bad or something is probably wired wrong. Assuming you ruled out the clutch by directly wiring it.
As far as how much to charge it, IDK what "volume" is specified. I typically charge using gauges as a guide but I also put a thermometer in one of my vents and stop when it gets the coldest. My personal experience after converting entire company fleets of vehicles from R12 "back in the day" is that they cooled best slightly under the recommended charge from the conversion guide manual that was supplied back then. I had a charging station that could add or subtract refrigerant by 1/10 of a pound and we monitored the temp coming out of the vents. It would get colder up to a point and then start going back up. At that point we pulled a little back out to where it was coldest.
As far as how much refrigerant on these trucks........I don't think I've ever used an entire can of R134 in any of mine. I'm talking the ones Walmart sells. 11 or 12oz cans I think. I probably use most of what is in that size can. There's usually a little left.
Pressures depend on temperature and where you live matters. I'm in AZ and even when it's 110 or higher out here I think my high side gets to around 200 PSI when I'm charging. I don't remember what pressure the compressor vent valve blows off at but it will pop off if you go too high.
Sounds like you're making progress.
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So the vsv has adjustment? I'll get in there and try the amplifier nob . When I first set up the system the shader valve got stock open and I don't know how much refri got lost I think I might have put 2 cans in there . Wish I knew what the pressure is supposed to be I have a 86 book and it says the pressure but that's assuming it's r12 not 134 so I'm going to say the values should be different
The valve on the intake, not the electrical valve. It has a knob
So the top of of the idle valve where the spring is that's an adjustment nob?
Just to add, that idle up valve in the pic pappy posted above are often bad. If it doesn't change your idle speed when you adjust it ,it may be bad. They are getting old and the diaphragm inside fails. It won't keep your A/C from working though. It just doesn't kick up your idle to compensate for the load.
Ya, there is an o-ring that fails. It can be replaced. I have a bunch. Let me know if you need one. The diaphragm can too, but mostly it's the o-ring.
I returned it and found the correct replacement @ 22RE Performance for $31
Picture?
Running into another issue. Got everything installed. Vacuumed down as expected and held as expected. Began the process of putting in refrigerant by turning off valves, using the can sealer adapter to get the r134a ready and hooked everything up. Started the 4runner. Turned air to high and a/c on, slowly released refrigerant into the system, compressor kicked on, all was good. Obviously took some refrigerant but after a bit it wouldn't accept any more of the first can. Took maybe half of it. Compressor never stopped. What am I missing to get the system to accept more? Site glass has refrigerant moving around so I can assume it's on the high side but not sure what to do at this point. Entire system is brand new.
edit: for clarity, the air is getting colder but not cold inside. The evaporator is draining so their is a cooling effect happening. It's just that my low side pressure WILL NOT drop at all. I used the correct expansion valve from Denso. Not sure if that has something to do with what is going on or not.
edit: for clarity, the air is getting colder but not cold inside. The evaporator is draining so their is a cooling effect happening. It's just that my low side pressure WILL NOT drop at all. I used the correct expansion valve from Denso. Not sure if that has something to do with what is going on or not.
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Maybe the expansion valve is faulty?
