P0335: Crankshaft position sensor "A" circuit malfunction
The engine computer gets no valid signal from the crankshaft position sensor, which it needs to time the spark and injection. The engine can stall or fail to start.
Updated
What P0335 means
The crankshaft position sensor reads a toothed trigger wheel on the crankshaft. From it the engine computer knows the engine speed and where each piston is, which it needs to time the spark and the fuel injection.
P0335 means that signal is missing or doesn’t make sense. Many engines then can’t run at all; some keep running on the camshaft sensor’s signal instead.
Can I keep driving?
Drive gently
Drive gently and only as far as you need to, and have it checked soon. The engine can cut out without warning and may not restart; steering and braking then get much heavier. Avoid motorways and long trips until it’s fixed.
General guidance based on the code alone, not on the car’s actual condition. If in doubt, stop and ask a mechanic.
A stored P0335 on an engine that still runs usually means the signal drops out now and then. That can happen at any speed, without warning.
Symptoms
- The engine cranks but doesn’t start, or starts only sometimes.
- The engine stalls while driving, on some cars only when it’s hot.
- On some cars, the rev counter drops to zero or jumps while the engine runs.
Common causes
- Faulty crankshaft position sensor. Sensors can fail with heat and age, sometimes only when warm.
- Wiring or connector fault. The sensor often sits low on the engine, where its wiring is exposed to heat, oil and dirt.
- Damaged or dirty trigger wheel, or debris on the sensor tip. Metal particles on the sensor tip, or a damaged or loose trigger wheel, spoil the signal.
Typical fixes
- Check the sensor’s plug and wiring for damage, oil and corrosion.
- Remove the sensor and check its tip for metal debris and damage.
- Have the sensor’s signal checked while cranking, and replace the sensor if it’s faulty.
- If a new sensor doesn’t help, have the trigger wheel and the wiring to the engine computer checked.
Questions
Can I drive with P0335?
Gently, and only as far as you need to: the engine can cut out without warning and may not restart, and steering and braking then get much heavier. Avoid motorways and long trips, and have it checked soon.
Why won’t my car start with P0335?
Without the crankshaft signal, many engine computers don’t know when to fire the spark and inject fuel, so the engine cranks but doesn’t start.