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I have no idea how I acquired this document. It does seem authoritative - possibly came from a Toyota TSB. It spells out the oil and refrigerant quantities for R134a conversions on various Toyota vehicles. Get out your metric to SAE conversion charats. If you need help, I can convert g and cc to lbs and fl. oz. for you, for a fee. Ha ha. Ha ha ha ha.

View attachment 75414
Thanks, that should do it!
My 93 was already converted to 134 by the PO so I just need to fill the oil and charge it 馃憤
 

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75588

my lengths came out very different from yours, the short one is about 8 3/4" from the back of the stock fitting to the end of the new fitting, the long one is 13 3/8". Will update with lines installed soon.
 

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75589

she's all installed and working! however I now understand why you made the larger line a lot longer than mine. I failed to consider that cross bar that bolts in 2 spots on the frame. My AC lines now interfere with where that would be. Guess I'll have to make a new one, not a huge deal.
 

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1991 2GR SW20
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Any insight would be appreciated. I just vacuumed, leak tested and charged the system with 24oz of 134a replacement. To finish drawing the refrigerant out of final can, I had to jumper the AC clutch relay plug to kick on the compressor. However, the compressor won't kick on by itself. I have low side pressures of 80psi+. This should be adequate to kick on the compressor. The clutch relay checks out also. So do both pressure switches and the climate control switch. When I jumpered the clutch relay switch, it seems to cycle the fans as normal but drove the compressor constant.

Is it possible it isn't receiving rpm signal? It something else? I had my harness done by Doug at Wiregap. I am using a tach adapter from Rat2Motorsports wired into my harness, mounted next to my ecu. (5sfe -> 2gr)

Not sure what troubleshooting to do from here. System seems fully charged with no leaks.
 

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I've seen your other posts. The first one regarding the relay, and the newer one regarding the amplifier. The amplifier needs to trigger the ac clutch relay. There is a amplifier troubleshooting section in the BGB. If you don't have it or cannot find it I can get it for you (what year is your car.) If I recall correctly, the rpm signal for the amplifier comes from the instrument cluster aka combination meter. [I recalled incorrectly. There is no rpm signal to the amplifer. Corrected in later post, with details of how the amplifier detects engine running condition]. If your tachometer is displaying rpm then chances are the rpm signal is going from there to the amplifier ok - but this bears verifying. You can use a test light on the rpm terminal on the amplifier to verify. The signal from cluster to amplifier is not affected by the 2GR harness or ECU. LIke the radiator fans, it functions completely independently of the ECU. On my car I had an amplifier issue that affected the fans, not the compressor. I was able to get a replacement amplifier from a partout, and fortunately it worked. Your other option if you have an amplifier fault and you cannot find a replacement amplifier is to wire a dash toggle switch in-line with the pressure switch to trigger the ac clutch relay. This way you do not risk burning up your compressor if you have too much or not enough refrigerant pressure.
 

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I have a related question on getting the A/C working on my 2GR swap ('93 NA chassis, Sienna engine + ECU with the 1GR compressor). I have everything connected but do not have it evacuated and charged yet, so this is a bit of a pre-emptive question. I'm not intending to hijack this thread, if I need to move this to its own thread let me know. (.... though one of my questions is related to the mention of the RPM signal above.....).

When I was doing my wiring I noticed an A/C Thermistor (A14) input running through the EA1 connector to the old engine ECU, "THE" input. I have not done anything with that, and am wondering whether it is needed for anything ?: (I noted on the HVAC schematic that the same A14 Thermistor is connected to the A/C Amplifier, though seems different terminals of the thermistor are used).... Engine ECU is shown below:
76756


This is separate from the ACT / ACA terminals running between the old engine ECU and the A/C amplifier...

SO the questions are :
(1) is there any use for those terminals (1 & 2) of the A14 / AC Thermistor in the 2GR swap, and
(2) do I need to do anything with the "ACT" input to the A/C amplifier to allow normal operation, and
(3) For my '93's A/C system, I do not see any mention of an RPM signal (from the cluster, or otherwise - even for the 3S-GTE) running to the A/C amplifier. Was that only applicable for earlier years ? I will try to find an earlier schematic to make sure....

Thanks in advance,
 

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Is it possible it isn't receiving rpm signal? It something else? I had my harness done by Doug at Wiregap. I am using a tach adapter from Rat2Motorsports wired into my harness, mounted next to my ecu. (5sfe -> 2gr)
This may be a dumb question, but are you trying to do all this with the engine idling, fully warmed up? The reason I ask is, the A/C in my 2GR swapped car won't kick on with the engine idling. It will cool fine if it's on, but if you try to turn it on at idle, you have to blip the throttle just a tiny bit (raise the RPM to about 750-800) before it will turn on. It seems the 2GR idles too low to kick it on.

Sorry that I was mistaken with regard to the RPM signal. I mixed it up with another car. It appears that the amplifier determines the engine condition (running or stopped) based on voltage on pin 18. This is from the 93 Repair Manual.
I believe that is somethign else, as pin 18 on the A/C amplifier is the radiator temp sensor, according to the wiring diagram. The amplifier has an input directly from the igniter on pin 5, and in my experience the A/C kicking on or not is RPM dependant, more than just engine on / off.
76758


Not sure why it says the IGN input is only for the 3S-GTE, seems odd that it wouldn't have an RPM input with the 5S, unless it gets it from the engine ECU on the 5S via pin 2:
76759


Could be that on the NA it's not an RPM signal and is in fact just an on/off. I wonder if you need to hook up power to pin 2?

I wonder if hooking up power to pin 2 on MY car would get rid of the need to blip the throttle to turn the A/C on at idle...
 

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This is an update with regard to fittings for MY 94 and 94. The fittings for the ac lines at the firewll are a different size from 91-93 listed earlier in this thread.

93 and earlier fittings are 7/8-14 and 3/4-16, the ones on the 94-95 22 & 24mm.

Fittings for the 94-95 may be available here but this has yet to be tested.
https://coldhose.com/collections/female-oring-metric
 

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So if I'm reading this correctly you order the following hoses:
FOUR SEASONS 55414
FOUR SEASONS 55189

A/C fittings:
RB-1307
RB-1312
(RB-1302 optional for 1312 if you don't feel like clocking line, will have to bend straight fitting)

Cut the ends off the hoses to length measured from end of compressor side fitting:

55414 #8 = 9-3/4"
55189 #10= 8-1/4

Have fittings crimped on and install to:

DENSO 4711413
using 7.75 oz Ester oil
Where did you get the 7.75oz of ester oil from? I can鈥檛 find this quantity published anywhere. The charts says 140cc of oil which is about 4.7oz. Thanks!
 

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Where did you get the 7.75oz of ester oil from? I can鈥檛 find this quantity published anywhere. The charts says 140cc of oil which is about 4.7oz. Thanks!
It's been too long, I can't remember. Could be another thread, could have been denso website. I did get it from someplace though.
 
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