Crankshaft Position Sensor Circuit Malfunction
In short
P0335 means the computer isn't getting a proper signal from the crankshaft position sensor — the sensor that tracks engine speed and crank position and is the primary trigger for spark and fuel. Because the engine essentially can't run without it, this code often comes with stalling or a no-start. The usual cause is a failed crank sensor, but a damaged connector/wiring, a cracked reluctor (tone) ring, or oil/debris on the sensor can also trip it.
Is it safe to drive with P0335?
Not reliably. The crankshaft position sensor is essential for the engine to run, so P0335 commonly causes stalling while driving or a failure to start at all. You could be stranded without warning. Get it diagnosed before depending on the vehicle; it won't damage the engine, but it can leave you stuck.
Symptoms
- Check engine light on (may not illuminate if the engine won't start)
- Hard starting, no-start, or long cranking
- Stalling while driving, sometimes intermittent
- Rough running, hesitation, or surging
- Tachometer dropping to zero or behaving erratically while running
Common causes (most → least likely)
How to diagnose it (before buying parts)
- 1 Inspect the crank sensor connector and wiring for corrosion, oil, chafing, or heat damage — it's often mounted low and exposed.
- 2 Note the pattern: if the engine stalls when hot and restarts once cooled, that's classic heat-sensitive crank-sensor failure.
- 3 With a scan tool, watch RPM while cranking — if RPM reads zero or drops out, the computer isn't getting the crank signal.
- 4 Check the sensor's power, ground, and signal at the connector per the wiring diagram; an open or shorted circuit points to wiring rather than the sensor.
- 5 If a new sensor and good wiring don't resolve it, inspect the reluctor/tone ring for damaged teeth or runout.
Repair options & cost
By manufacturer
Crank sensor failures are common and frequently heat-related. Use an ACDelco/OEM sensor; some engines need a quick crank-variation relearn with a scan tool after replacement.
VQ-series crank/cam sensor failures are well known — OEM (Hitachi) sensors are the dependable fix.
Usually the sensor itself or its connector; use Denso/OEM and check for oil contamination from a nearby leak.
Heat-sensitive crank sensors that cause hot no-starts are a classic complaint; replace with OEM-quality parts.
Frequently asked questions
What does the crankshaft position sensor do?
It measures how fast the crankshaft is turning and its exact position, which the computer uses as the master trigger for ignition spark and fuel injection. The engine essentially can't run without a valid signal — which is why P0335 so often means stalling or a no-start.
Can I drive with P0335?
Not reliably. The car may stall without warning or fail to restart, leaving you stranded. It doesn't damage the engine, but you should diagnose and fix it before counting on the vehicle.
Why does my car stall when hot but start when cold?
That's the classic symptom of a heat-sensitive crankshaft position sensor: as it heats up, the internal element fails and cuts the signal; once it cools, it works again. A new sensor usually fixes it.
Is it the sensor or the wiring?
Most often the sensor, but always check the connector and wiring first — they're frequently mounted low near heat and road grime, where corrosion or chafing can mimic a bad sensor.