Q: 2013 Ford Fiesta overheating when ac is on? The air coolant has a peanut butter consistency & color?

asked by on June 27, 2017

My 2013 Ford Fiesta is over heating only when I turn on my A/C. I also noticed that the place where the antifreeze goes is clogged up with some brown stuff that looks exactly like peanut butter, same color & consistency. I tried draining that out but there's still a lot more in there & I don't know how to drain it all out completely so I can put new antifreeze on there. No engine lights are on. But it does need a new oil change. What could the problem be?

My car has 666654 miles.
My car has an automatic transmission.

AC Compressor Replacement $715.49 - $3134.49 Get a Quote
Radiator Replacement $353.55 - $1403.40 Get a Quote
Water Pump Replacement $187.27 - $1236.57 Get a Quote

Hi There, Overheating with the AC on is generally caused by a couple of possibilities. When the AC compressor is beginning to fail, this may incur an increased load on the motor as it works harder than usual to turn a bad compressor. This increased load causes the motor to work harder than it otherwise normally would, resulting in the motor overheating. The other possibility may be a cooling system that is not working efficiently. This may be caused by a clogged radiator, blocked or clogged radiator condenser fins, a water pump that is not pumping correctly or potentially cooling fans that are not working properly.

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