1996 honda accord lx. 2.2l 4 cylinder. 185xxx miles

the D4 light on my 96 accord hasnt worked since ive bought it. idk whats up, maybe its just the bulb? i know it blinks if the tranny is bad... and it shifts kinda hard sometimes and feels like maybe the tranny is creating drag? the drag starts up at about 50mph and the rpms stay at a constant 2k+ at that speed, even if i barely press the gas pedal. i was thinking i could replace the tranny fluid and if that doesnt help maybe changing the torque converter solenoid? the car also makes a weird vibrating whizzing hum noise in the first few gears. it has the most trouble shifting from 2nd to 3rd. im averaging about 20mpg and id like to get better mileage. any insight on the issue would be appreciated, thanks (: also is there a way i could override the auto tranny to shift when i want it too?

 

The D4 light flashing means the PCM has detected a problem and has stored a code. Stop by any parts store and they will scan for codes. Your connector is behind the ash tray. Post the code(s) on here. They start with the letter P and have four numbers, like P1234.

To override the shift, start out with the gear selector in low, shift to D3, the D4.