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clinebarger · 09-13-2016, 10:38 PM

Rob, Have you tested the A/C Request? While watching A/C Request PID on your scanner, Turn the Vintage Air on & see if it changes from "No" to "Yes". Check for 12vdc on the Request Wire if still "No".

If we can't get a valid Request, No need in leaving it wired the way it is now.

Recap if the Request doesn't work out.....

Vintage Air Compressor Clutch wire too the VA Binary, Binary too the Compressor. Will provide High & Low Pressure protection.

The Transducer & PCM will provide Fan Control as needed.

Up the Base Idle as needed, This can get weird with a stock stall converter upon decal to a stop. The PCM's seem to "learn" & act right after a few miles. I'm sure a good tune could correct this.

Your Compressor should have around 2 oz in it, This is just an average based on my experience servicing GMT800 Trucks.
If I decided to go this route, I'd be concerned about using Too Much Oil! And would add 3 to 3 1/2 ounces, The Denso Compressor is VERY good design & can cope with a little less oil, Where too much oil will affect A/C performance.....More so with aftermarket units.

I would (If it were mine) Drain & Flush the Compressor. Use High Volatility/Flammable/No Residue A/C Flush, The good stuff, Kills baby Seals & such. While turning the Compressor....Flush all the residual oil out.

Add 6 ounces of PAG 46 too the Compressor, After installed, Spin it at least 20 times. Deep Vacuum for at least 12 hours.

Start with 28 ounces of 134a, You will probably end up with 2-2.25 pounds to get maximum chill.

09-13-2016, 10:38 PM	#46
clinebarger Senior Member Join Date: May 2009 Location: Fort Worth, TX Posts: 6,370	Re: Need some help with tuning. Rob, Have you tested the A/C Request? While watching A/C Request PID on your scanner, Turn the Vintage Air on & see if it changes from "No" to "Yes". Check for 12vdc on the Request Wire if still "No". If we can't get a valid Request, No need in leaving it wired the way it is now. Recap if the Request doesn't work out..... Vintage Air Compressor Clutch wire too the VA Binary, Binary too the Compressor. Will provide High & Low Pressure protection. The Transducer & PCM will provide Fan Control as needed. Up the Base Idle as needed, This can get weird with a stock stall converter upon decal to a stop. The PCM's seem to "learn" & act right after a few miles. I'm sure a good tune could correct this. Your Compressor should have around 2 oz in it, This is just an average based on my experience servicing GMT800 Trucks. If I decided to go this route, I'd be concerned about using Too Much Oil! And would add 3 to 3 1/2 ounces, The Denso Compressor is VERY good design & can cope with a little less oil, Where too much oil will affect A/C performance.....More so with aftermarket units. I would (If it were mine) Drain & Flush the Compressor. Use High Volatility/Flammable/No Residue A/C Flush, The good stuff, Kills baby Seals & such. While turning the Compressor....Flush all the residual oil out. Add 6 ounces of PAG 46 too the Compressor, After installed, Spin it at least 20 times. Deep Vacuum for at least 12 hours. Start with 28 ounces of 134a, You will probably end up with 2-2.25 pounds to get maximum chill.