AC, mixing old and new?
11-20-2010, 07:40 AM
#1
AC, mixing old and new? I'm putting an 05 5.3 engine in a 72 cutlass. There's a complete A/C system from an f body for sale, hoses, condenser, evaporator, etc.
I was thinking about swapping the cutlass evaporator out for the f body and using the rest of the f body stuff, and hooking to the 05 truck compressor. It would be hooked it to the 05 truck computer too.
But to control it I'm thinking about keeping the cutlass dash controls.
Questions:
It looks like the 72 cutlass uses a thermostat temp sensor wired into the compressor + wire to turn it on/off. I suspect the f body uses a temp sensor that controls the AC request voltage to the computer. Should I wire the thermostat into the AC request wire?
The truck AC system shows an additional low pressure switch. What's the function of this when there's already the pressure sensor?
Anyone see any other problems with this setup?
I was thinking about swapping the cutlass evaporator out for the f body and using the rest of the f body stuff, and hooking to the 05 truck compressor. It would be hooked it to the 05 truck computer too.
But to control it I'm thinking about keeping the cutlass dash controls.
Questions:
It looks like the 72 cutlass uses a thermostat temp sensor wired into the compressor + wire to turn it on/off. I suspect the f body uses a temp sensor that controls the AC request voltage to the computer. Should I wire the thermostat into the AC request wire?
The truck AC system shows an additional low pressure switch. What's the function of this when there's already the pressure sensor?
Anyone see any other problems with this setup?
11-20-2010, 06:31 PM
#4
If your 2005 5.3 is from a truck, then it won't have an A/C request wire, it's run on a serial data line, and the only way to get it to turn on is to run the truck A/C controls. I tried for a long time to get it to work on my 2003 6.0, but finally just bypassed the PCM all together.
11-21-2010, 02:04 AM
#5
I saw that wire labelled serial data, I just assumed it was just a request wire. Guess I'll just go with an aftermarket system.
If your 2005 5.3 is from a truck, then it won't have an A/C request wire, it's run on a serial data line, and the only way to get it to turn on is to run the truck A/C controls. I tried for a long time to get it to work on my 2003 6.0, but finally just bypassed the PCM all together.