Air Conditioning problem
1989 Ford Station Wagon V8 Two Wheel Drive Automatic 106789 miles
My A/C system will only work well at idle condition. When the engine is even under the slightest load; the fan shuts off and the air becomes warm. Only after returning to idle or unloaded conditions does the system return to normal. I've checked the vacuum tank ( " coffee can" ) and that holds good vacuum; I was thinking the vacuum check valve may be bad but I wouldn't think that would effect fan speed. Any thoughts?