Drives fine until I get to around 20mph then it begins to rev high and not shifting or gaining speed.
My car has 122000 miles.
My car has an automatic transmission.
Hello - the lack of an upshift from 1st to 2nd could be dirty, burned fluid or clogged filter, or a failed Shift Solenoid "A". Low fluid level and low electrical system voltage can also make the transmission misbehave as you are experiencing. I would recommend a transmission inspection 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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