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Nissan Altima Radiator/AC woes Help

A month or so ago my AC kept cycling off while driving at high speed on very hot day. The shop checked and said everything looked fine and that the car can do that automatically to protect itself.

Yesterday AC quit while driving, about 20 - 25 minutes later temperature gauge went to hot. I pulled off at the first exit - the first thing I saw was a Ford dealership. I stopped and had the service manager look at it with me. Fluid was coming out of the radiator, specifically leaking on the lower driver’s side. (no steaming or such) The car is now 60 miles from home at the Ford dealership.

Question 1. Can the computer cycle the AC off when needed?

Question 2. Was that cycling likely related to a radiator issue developing?

Question 3. How likely it is that I need a new radiator - is it possible it is just a connection that is leaking?

Now for the twist – last winter my EX-dealership service dept. did a major service and flushed the transmission fluid and did not properly clamp the thing. It leaked, I griped, they towed, fixed and cleaned it up.

Final question! Is it possible that the two issues are related? The leak from the transmission issue was at nearly the same location as the current one!

PS — my current shop is at a Nissan dealership that appears as a recommended site… if only I could have gotten back home…

You didn’t tell us the age or mileage of your Altima. This information might help.

It’s normal for the AC compressor to cycle on and off. It does not run constantly. It runs until the system pressure is correct, then stops running until the pressure drops to a specified level, at which point the compressor starts compressing again.

The AC system is designed to shut off the compressor if there is insufficient refrigerant in the system. This is to avoid destroying the compressor, since the refrigerant also acts as a compressor lubricant. Low refrigerant level will also cause poor cooling. The only way to check is to hook up a set of AC gauges. Have someone check the refrigerant level.

I think you may have a cooling fan problem, which could explain the AC trouble and the engine overheating.

Other things that can cause engine overheating are a bad thermostat, leaking coolant hoses, or a bad head gasket.

It’s unlikely that last winter’s transmission flush is causing your engine to overheat. What was leaking from the radiator? Was it coolant or transmission fluid?

Sorry for the missing info. 2006 with about 46K. When I said the compressor turned off - I mean that the whole thing turned off, compressor and zero cold air came out - the air became quiet warm and the AC stayed off for several minutes at a time.

The original leaking was transmission fluid, after heating up the other day it was fluid from the radiator with antifreeze in it.