What the customer told us
Car would rev high and barely move from a stop, then catch and drive normally. Another shop told her the CVT was going and quoted a replacement unit.
What we found
No internal noise, no metal in the pan, and the fluid was dark but not burnt. Scan data showed the secondary speed sensor dropping out intermittently under load, which makes the transmission controller default to a protective mode. We backprobed the sensor circuit and watched the signal drop on a live graph while flexing the harness.
What we did
Replaced the secondary speed sensor and repaired a chafed spot in the harness where it had been rubbing on a bracket. Performed a full CVT fluid exchange with genuine NS-3 fluid and relearned the adaptive values.
How it came out
Shifts smoothly from a stop with no flare. We drove it about twelve miles including highway and stop-and-go. She spent $310 instead of $4,200.
Parts fitted
- Secondary speed sensor
- CVT fluid (NS-3)
- Harness repair materials
Photos to add: Live scan data showing the sensor dropping out; Chafed harness found against the bracket; New sensor installed and harness protected; Clean CVT fluid after the exchange.
