Q: Check engine light on and code P1791 showing when connected to scanner. 1997 Acura TL

asked by on December 04, 2016

Connected scanner to obd2 port after check engine light came on, code P1791 came up and says it automatic trans axle concerns. Please advise on what route to go. I can fix the car my self just need to know location and what parts to get

My car has 145680 miles.
My car has an automatic transmission.

Gears slipping when accelerating Inspection $94.99 - $114.99 Get a Quote

Hello - the P1791 code indicates a problem with an internal speed sensor (or governor) within the transmission. This device provide RPM information from the transmission to the transmission controller - which determines when the transmission shifts up to the next gear. You may have noticed that the engine is revving higher before shifting in Drive. I would recommend an inspection of the transmission by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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