My toyota lucida automatic gas just had a new engine and a new gear box. But now its really struggling to shift gears an theres a lot of black smoke coming from the back end an its making the back door black all the time
It sounds like the gearbox is doing as commanded ie. late shifts due to full throttle with not enough engine power to reach shift points. Check engine making sure all electric sensors are on. The black smoke is too much fuel or unburnt fuel. Check pump timing etc. I'm a gearbox guy not engines so please seek more help from engine supplier.
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