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Q: When cold the car misses. Later in the day it runs good. This is a new car to me recently purchased. Morning temps are mid 40's

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When I fist start and run the car in the morning it missed alot. Later in the day it it runs very good.

My car has 156000 miles.
My car has an automatic transmission.

A: Hello there, many different faults can caus...

Hello there, many different faults can cause your 2004 Hyundai Santa Fe to run poorly when cold. The most likely faults would be a stuck open thermostat, coolant temperature sensor, oxygen sensor, vacuum leak, or exhaust leak. A qualified technician from YourMechanic will be able to diagnose your rough running when cold issue and make any repairs required.

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