My 2001 automatic Miata idles really rough at stoplights ...

Q: My 2001 automatic Miata idles really rough at stoplights when I run the AC, but not when it is off.

asked by on August 04, 2017

When I stop at stoplights with my AC on and the transmission engaged, the car idles very rough. When driving or when in park with AC on it runs smooth with no problem. I just had all new belts installed, plus a new flex/fly wheel in the transmission. My mechanic says I now need a new AC compressor and a two other parts to fix this problem. Does this sound like the correct solution?

My car has 73000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. Two aspects about the issue lead me to believe the previous technician is correct. To start, the compressor is the only component that will effect the engine, as it is the part connected to the engine via the drive belt (which is turns powers the entire AC system). If the compressor is causing extra strain on the drive belt and engine, everything else the drive belt and engine are connected to are also effected. This causing many issues. Secondly, the drive belt was just replaced, so we know it is not a drive belt issue. As to the other components he wants to replace, there is no way to tell if that is needed or not. For a quote or help from our team, contact the service department to schedule an appointment.

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