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Intermittent A/C

My mum just had her Crank Sensor and Ignition Module replaced ('98 Pontiac LeMans w/ 55K miles) because the car was dieing suddenly. That may have fixed the dieing problem but since she got it back the A/C doesn’t come on for a varying period and then goes on and off. This applies to the fan as well as the compressor so it seems to me it is an electrical or electronic issue. I guess she should take it back to the guys who did the work but I was hoping maybe someone had experienced this before.



Thanks,

tenthumbs



You need to get the pressures checked. In 11 years, enough refrigerant may have leaked out causing pressures below the threshold of the low-side cutoff switch. This would cause the turning on and off.

Low pressure wouldn’t turn the cabin fan off. The OP is right. It is an electrical problem.

The pressures were tested in '04 and coolant checked/added. When it is working it blows good cold air so that is why I think it is electrical. I’m thinking this might be something to take to the dealer rather than the independent she has been going to.