A/C problem
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
I wrote this up awhile back for this problem.
On at least later C3 the problem is that heater is the default position (no vac. or vac. leak) due to being designed in the north. Vent should be default. Very safe bet the problem is 1 OR 2:
1) The vac. line from engine may be damaged from heat - a small plastic tube that goes in pass. side of dist. below the hood alarm switch into wiper valley. Replacing most of engine side w/ hose will normally fix. OR
2) The vac. switch itself is not switching due to vac. leak as the usually plastic rivet is not holding the 2 main switch parts together well. Besides replacing, it is also possible to tighten this &/or disassemble to lube w/ a thin layer of white lithium grease to fix. Try pressing the 2 halves of the switch together to test in A/C or VENT w/ engine running.
3) If you have a heater, the small vac. tube to heater hose valve under hood may be damaged from heat & need replacing. Block w/o heater.
PS The design problem comment is not intended to be offensive to any of our northern friends
On at least later C3 the problem is that heater is the default position (no vac. or vac. leak) due to being designed in the north. Vent should be default. Very safe bet the problem is 1 OR 2:
1) The vac. line from engine may be damaged from heat - a small plastic tube that goes in pass. side of dist. below the hood alarm switch into wiper valley. Replacing most of engine side w/ hose will normally fix. OR
2) The vac. switch itself is not switching due to vac. leak as the usually plastic rivet is not holding the 2 main switch parts together well. Besides replacing, it is also possible to tighten this &/or disassemble to lube w/ a thin layer of white lithium grease to fix. Try pressing the 2 halves of the switch together to test in A/C or VENT w/ engine running.
3) If you have a heater, the small vac. tube to heater hose valve under hood may be damaged from heat & need replacing. Block w/o heater.
PS The design problem comment is not intended to be offensive to any of our northern friends
Thread Starter
Intermediate
Joined: Jan 2010
Posts: 44
Likes: 0
I wrote this up awhile back for this problem.
On at least later C3 the problem is that heater is the default position (no vac. or vac. leak) due to being designed in the north. Vent should be default. Very safe bet the problem is 1 OR 2:
1) The vac. line from engine may be damaged from heat - a small plastic tube that goes in pass. side of dist. below the hood alarm switch into wiper valley. Replacing most of engine side w/ hose will normally fix. OR
2) The vac. switch itself is not switching due to vac. leak as the usually plastic rivet is not holding the 2 main switch parts together well. Besides replacing, it is also possible to tighten this &/or disassemble to lube w/ a thin layer of white lithium grease to fix. Try pressing the 2 halves of the switch together to test in A/C or VENT w/ engine running.
3) If you have a heater, the small vac. tube to heater hose valve under hood may be damaged from heat & need replacing. Block w/o heater.
PS The design problem comment is not intended to be offensive to any of our northern friends
On at least later C3 the problem is that heater is the default position (no vac. or vac. leak) due to being designed in the north. Vent should be default. Very safe bet the problem is 1 OR 2:
1) The vac. line from engine may be damaged from heat - a small plastic tube that goes in pass. side of dist. below the hood alarm switch into wiper valley. Replacing most of engine side w/ hose will normally fix. OR
2) The vac. switch itself is not switching due to vac. leak as the usually plastic rivet is not holding the 2 main switch parts together well. Besides replacing, it is also possible to tighten this &/or disassemble to lube w/ a thin layer of white lithium grease to fix. Try pressing the 2 halves of the switch together to test in A/C or VENT w/ engine running.
3) If you have a heater, the small vac. tube to heater hose valve under hood may be damaged from heat & need replacing. Block w/o heater.
PS The design problem comment is not intended to be offensive to any of our northern friends
Thanks, I will dig into it in the morning and see if I can find the problem.
Pro
Joined: May 2011
Posts: 581
Likes: 5
From: BC
Steve g
Thread Starter
Intermediate
Joined: Jan 2010
Posts: 44
Likes: 0
I have got to have the worst luck. I have a new A/C compressor installed last year. Never used the A/C until I started working on this problem. The A/c felt good on my feet so last night when me and the Wife were going to a car show I turned the A/C on for the first time. About 15 minutes later the compressor quit and the fan belt burned up. Just my luck.
