Could a leak in the ac system cause my engine to overheat when ideling. Because my engine was overheating to almost the red line when ideling threw town and the ac was blowing hot so I added a can of freon then drove threw town the next day and temps never rose above 210. Few days later same thing happens so add more freon psi was at 26 on the freon guage then alls good again.

 

No, an AC leak will not cause your car to over heat if everything is working right. But if your engine temp sensor is not kicking on your fan but the AC system was kicking on the fan then it is possible. If that is what is happening than you should have the same reaction if the AC is just turned off. You should verify your fan is coming on with the AC being off.

 

Now my Ac compressor is bad it makes a grinding noise when it kicks on. But now I can idle all day and the temps never get above 210. So is this my problem.

 

Idle all day with or without the AC on? Like Gorn said, you need to verify the fans are coming on without the AC running.