Common reasons
*Low Transmission Fluid (ATF): Low or contaminated ATF can cause clutches to slip and drag on the transmission.
* Worn Clutches: Over time, clutches in a transmission can wear out, causing them to slip and drag when changing gears.
* Defective torque converter: The torque converter transfers power from the engine to the transmission. Its malfunction can cause the transmission to slip.
*Solenoid Problems: Solenoids control the flow of ATF in the transmission. Their malfunction may interfere with gear shifting.
Honda specific reasons
*Input Shaft Speed Sensor Problem: A faulty input shaft speed sensor can send incorrect information to the Transmission Control Module (TCM), causing the transmission to tighten.
* Main pressure valve malfunction: The main pressure valve regulates the ATF pressure in the transmission. If it malfunctions, it may result in insufficient pressure and tightening of the transmission.
*Line Pressure Solenoid (LPS) wear: The LPS solenoid regulates ATF pressure in clutches. Its wear can cause clutches to slip and the transmission to tighten.
* Dirty ATF Filter: A dirty ATF filter can restrict fluid flow, causing the transmission to slip.
Other Possible Causes
*Wiring Problems: Faulty wiring can interfere with transmission operation.
*TCM malfunction: The TCM controls the transmission. Its malfunction can lead to problems with gear shifting.
*Mechanical Problems: In rare cases, mechanical problems such as broken gear teeth or damaged transmission housing can cause the transmission to tighten.