What P0718 means
The input or turbine shaft speed sensor – a Hall sensor with square-wave output or an inductive sensor with sine output – reports the speed behind the torque converter.
How the engine computer detects it
With output and engine speed it gives the actual gear ratio, converter slip and shift timing. P0718 means the signal is present but jumps or drops out briefly. Ford's gasoline modules from 2012 to 2023 count 200 turbine speed spikes above 400 rpm with at most 1.5 s between them in a forward gear. GM's Honda-built five-speed of 2006 flags jumps of more than 3 mph per 10 ms three times in 500 ms, after two trips; GM's own transmissions file such jumps under P0716 instead. Loose contacts and electrical interference are the usual causes; shifts become erratic and limp mode may follow at times.
Written from public technical sources and not yet checked by a mechanic. How we write these pages
Symptoms
- Occasional harsh or unexpected shifts
- Warning lamp
- Converter clutch applies and releases unevenly
- Limp mode at times
Common causes
- Loose contact, corroded connector or chafing Most likely
- Electrical interference (shielding, ground, added consumers) Possible
- Metal debris on the sensor or loose mounting Possible
- Sensor faulty internally (temperature-dependent) Possible
How to diagnose P0718
- Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
- Inspect the parts involved: input speed sensor, sensor wiring, transmission control module.
- Work through the causes above from most to least likely, cheapest checks first.
- Clear the code and drive a full drive cycle to confirm the repair held.
Reading the code
- P
- Powertrain
- 0
- Generic (SAE) code
- 7
- Transmission
- 18
- Specific fault
Questions drivers ask
Can I drive with code P0718?
Drive gently and only as far as you need to. The engine computer may limit power to protect the engine, so avoid highways and heavy traffic until it's fixed. If the check engine light starts flashing, pull over.
Will my car pass an emissions inspection with P0718?
Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.
Can I fix P0718 myself?
Often yes, with an OBD-II scanner and basic tools. Difficulty: medium. Start with the cheapest checks before replacing expensive parts.
Often reported together
Codes that owners mention in the same NHTSA complaints as P0718. They can point to a shared cause, so it's worth checking them together.
This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.