I have a 2001 Honda Civic LX, automatic transmission. There are 3 gear settings: 2, D3, and D. If I'm driving in D3 and shift into D, I can feel it shift gears up (from 3 to 4), but then it immediately shifts up to 5. If I slow down (with it still in D), it doesn't shift to 4, but instead stays in 5 and the RPMs get real low. Hitting the gas again is very unresponsive (naturally, since it's high gear/low speed), but if I floor it, it'll drop down to gear 3. It just doesn't seem to want to stay in 4th. So when I'm going 55 mph in D, it's in 5th gear, and the RPMs are low (less than 2000). Doesn't seem like that's good for the engine. Is it a bad transmission, or can something just be re-calibrated? Or something else?
It look like if the torque converter is used ,his contained oil is too much fluid. This is normal maintenance, but this need to remove the gearbox frome the car, a bit tricky, need a mechanic.
An expiremented guy can easily give you this diagnostic if he test the car by driving it. Ask someone for that before do anything.
Could be the 3-4 upshift solenoid as well as the torque convertor clutch solenoid is bad? The upshift solenoid failing would explain why 4th doesn't stay engaged and if the torque remains engaged when downshifting could explain the low rpm. I would be interested about the 7 major problems -sounds like major money for mechanic... I would take it to a transmission specialist first.