Lately, my Civic’s automatic transmission won’t go into lock-up at highway speeds and there goes my 35 miles per gallon highway without it. Any suggestions on why the lock up convertor won’t engage?
Check your transmission fluid if low. Next if really dirty(should be reddish) change it. Cross your fingers.
Otherwise mechanic. Your check engine light on or is this a 1982 Civic??? You left out a critical piece of information in lack of year.
Remember it could be a simple repair still and hopefully it has thrown a code in a form of Check engine light or flashing D.
Tcc lockup? Trans does go into OD? Tcc not engaging is better than tcc being stuck on. That would stall motor.