Possible reasons for a long delay when shifting automatic transmission gears:
1. Low or dirty transmission fluid:
– This can lead to insufficient lubrication and overheating of the system, which will slow down gear shifting.
2. Faulty input shaft speed sensor:
– This sensor tells the transmission the speed of the engine and wheels, allowing it to shift gears accurately.
3. Faulty output shaft speed sensor:
– This sensor tells the transmission how fast the output shaft is rotating, which also helps it determine when to shift.
4. Faulty shift solenoid:
– Shift solenoids control the flow of fluid through the transmission to change gears. A faulty solenoid can slow down shifting.
5. Clogged or dirty transmission fluid filter:
– This may restrict fluid flow and cause delays in switching.
6. Worn or broken brake band/clutch:
– These components transfer power from the engine to the transmission. Wear or damage can make it difficult to shift gears.
7. Faulty Transmission Control Module (TCM):
– The TCM controls the operation of the automatic transmission. A malfunction may result in incorrect gear shifting.
8. Transmission mechanical failure:
– Serious internal problems such as worn gears or bearings can cause slow shifting.
Diagnosis and solution to the problem:
1. Check the level and condition of the transmission fluid.
2. Scan the vehicle for trouble codes that may indicate faulty sensors or solenoids.
3. Physically inspect the shift solenoids and transmission fluid filter.
4. If the problem persists, contact a qualified mechanic for further diagnosis and repair.
5. In some cases, the transmission may need to be overhauled or replaced.