Common Causes of P0335 Engine Speed Sensor Failure by Vehicle Make and Model

Seeing a P0335 code pop up on your scanner can be frustrating, especially when your car starts stalling, hesitating, or refusing to start altogether. This trouble code points to a problem with the crankshaft position sensor circuit a component your engine relies on to know the exact position and speed of the crankshaft. Without it, your engine's computer can't time the ignition or fuel injection properly. Getting this fixed quickly matters because driving with a faulty crankshaft sensor can leave you stranded or cause damage to other engine components over time.

What Does the P0335 Code Actually Mean?

P0335 stands for "Crankshaft Position Sensor 'A' Circuit Malfunction." The engine control module (ECM) monitors the signal coming from the crankshaft position sensor (CKP). When that signal is missing, erratic, or out of range, the ECM sets this code. The sensor reads a reluctor ring mounted on the crankshaft and sends voltage pulses to the ECM, which uses that data to calculate engine speed and crankshaft position.

If the ECM doesn't receive a clean signal, it may trigger engine stalling and other performance issues that make the vehicle unsafe or undrivable.

Why Does the Crankshaft Position Sensor Fail?

Several things can cause a P0335 code. Here are the most common reasons:

Worn or damaged sensor: Over time, the sensor's internal circuitry can degrade from heat and vibration.
Damaged reluctor ring: If the tone ring on the crankshaft has a chipped or missing tooth, the signal becomes irregular.
Wiring problems: Frayed wires, corroded connectors, or broken pins between the sensor and ECM are frequent culprits.
Poor ground connection: A weak or corroded ground can distort the sensor signal.
Timing chain or belt issues: If the timing has jumped, the reluctor ring position changes relative to the sensor, confusing the ECM.
ECM failure: Rare, but possible. The control module itself could have internal faults.

Some vehicles are more prone to this code than others. For example, if you drive a Chevy Silverado, you might want to check out this Silverado-specific P0335 troubleshooting guide for model-specific details.

What Symptoms Should You Watch For?

P0335 rarely shows up alone without symptoms. You'll likely notice one or more of the following:

Engine cranks but won't start
Intermittent stalling, especially at idle
Rough idle or misfires
Reduced acceleration or hesitation
Check engine light illuminated
Poor fuel economy

If your engine stalls unexpectedly while driving, that's a serious safety concern. Address this code as soon as possible rather than waiting for it to worsen.

What Tools Do You Need to Fix P0335?

Before you start, gather these tools:

OBD-II scanner
Digital multimeter (DMM)
Socket set and ratchet
Wire brush and electrical contact cleaner
Replacement crankshaft position sensor (if needed)
Electrical tape or heat-shrink tubing
Vehicle-specific repair manual or access to a repair database

Step-by-Step Guide to Fixing Engine Speed Sensor P0335

Step 1: Scan and Document the Code

Connect your OBD-II scanner and confirm the P0335 code. Write down any other stored or pending codes, as they can point you toward the root cause. If you also see camshaft position sensor codes, the problem might involve timing rather than the sensor itself.

Step 2: Visually Inspect the Sensor and Wiring

Locate the crankshaft position sensor. On most vehicles, it sits near the crankshaft pulley, flywheel, or engine block. Check for:

Cracked or broken sensor housing
Oil or coolant contamination around the sensor
Frayed, melted, or pinched wires
Loose or corroded connector pins

A visual inspection catches a surprising number of problems. Don't skip this step.

Step 3: Test the Sensor with a Multimeter

Disconnect the sensor connector and set your multimeter to measure resistance (ohms). Compare your reading to the specification in your vehicle's repair manual. Typical resistance values for a CKP sensor range from 200 to 1,000 ohms, but this varies by manufacturer. If the reading is open (OL) or far outside spec, the sensor is bad and needs replacement.

You can also check for AC voltage output while cranking the engine. A healthy sensor typically produces 0.5 to 1.5 volts AC during cranking. No voltage means a dead sensor or broken circuit.

Step 4: Check the Wiring Harness and Connector

If the sensor tests within spec, the problem is likely in the wiring. Use your multimeter to check continuity between the sensor connector and the ECM connector. Look for:

Open circuits (no continuity where there should be)
Shorts to ground
Shorts between wires

Also inspect the ground wire and make sure it has a clean, solid connection to the engine or chassis.

Step 5: Inspect the Reluctor Ring

If possible, inspect the reluctor ring (tone ring) for damaged or missing teeth. On some vehicles, you can see it through the sensor mounting hole. On others, you may need to remove the sensor or a cover plate. A damaged reluctor ring causes inconsistent signals that mimic a bad sensor.

Step 6: Replace the Faulty Component

Replace whatever you've identified as defective sensor, wiring, connector, or reluctor ring. When installing a new crankshaft sensor:

Clean the mounting surface and sensor tip
Use the correct torque specification for the mounting bolt
Ensure the air gap between the sensor and reluctor ring matches the spec (typically 0.020 to 0.060 inches)
Reconnect the electrical connector firmly until it clicks

Step 7: Clear the Code and Test Drive

Use your OBD-II scanner to clear the P0335 code. Start the engine and let it idle for a few minutes. Then take the vehicle for a drive that includes idle, acceleration, and highway speed. After the test drive, rescan to confirm the code hasn't returned. If the ECM runs the crankshaft position monitor and passes, the repair is successful.

What Are the Most Common Mistakes When Fixing P0335?

A few errors can waste your time and money:

Replacing the sensor without testing it first: A new sensor won't help if the wiring is the real problem.
Ignoring related codes: Other stored codes can guide you to the actual cause.
Using aftermarket sensors of poor quality: Cheap sensors sometimes fail right out of the box or within weeks. OEM or high-quality aftermarket brands are worth the extra cost.
Forgetting to check the reluctor ring: This gets overlooked often but causes the exact same symptoms.
Not clearing the code after repair: The check engine light may stay on even after the fix if you don't clear it.

How Much Does It Cost to Fix a P0335 Code?

The cost depends on what's actually wrong:

Crankshaft position sensor replacement: $20–$100 for the part, $80–$200 for labor at a shop.
Wiring repair: $50–$150 depending on the extent of damage.
Reluctor ring replacement: $50–$300+ for parts and labor, since it often requires partial disassembly.

DIY repairs save significantly on labor. If you're comfortable with basic automotive electrical work, this is a manageable fix in your garage.

Can You Drive with a P0335 Code?

It's not recommended. A malfunctioning crankshaft position sensor can cause the engine to stall without warning at intersections, on highways, or in traffic. Some vehicles will enter limp mode, limiting speed and power. Others may not start at all after being turned off. If you must drive the vehicle to a shop, keep trips short and avoid highways.

Useful Tips for Preventing P0335 from Coming Back

Keep the engine clean around the sensor area. Oil leaks can contaminate the sensor over time.
Fix oil leaks promptly, especially those near the crankshaft area.
Use dielectric grease on sensor connectors to prevent corrosion.
During timing belt or chain service, have the reluctor ring inspected for wear.
If you replace the sensor, use OEM parts or trusted brands like RockAuto, Denso, or Bosch.

Quick Checklist Before You Call It Done

P0335 code confirmed with scanner
Visual inspection of sensor, wiring, and connector completed
Sensor resistance and AC voltage tested with multimeter
Wiring continuity and ground checked
Reluctor ring inspected for damage
Faulty component replaced with quality part
Code cleared and test drive completed
Rescan confirms no returning codes

If you've worked through every step and the code still returns, the issue may be deeper a stretched timing chain, internal ECM fault, or intermittent wiring problem that only shows up under specific conditions. At that point, professional diagnostics with an oscilloscope can catch what a multimeter might miss. You can also review this guide to common P0335 causes by vehicle to see if your specific make and model has known issues worth investigating further.