P0336 Crankshaft Position Sensor Range/Performance on Smart Fortwo 451 / 453
P0336 is a crankshaft position sensor range/performance fault — the intermittent version of P0335. The classic Smart pattern is a random stall followed by a normal restart, sometimes with no warning lamp at all. Connector and sensor are the cheap-first fixes. Owner reports suggest this often gets covered under powertrain warranty, so check your warranty status before paying out of pocket.
Typical Symptoms
- Check engine light with code P0336 (sometimes intermittent)
- Random stall, then a normal restart a few seconds later
- Stumble or brief cut-out at idle or low rpm
- Tach needle flickers under cranking
- Sometimes paired with P0335 or P0340
- No-start that clears on its own after the engine cools
What it means
The crankshaft position sensor (CKP) reads teeth on a reluctor ring spinning with the crank. P0335 is set when the signal is missing entirely. P0336 is set when the signal is there but the ECU sees gaps, noise, or timing that doesn't match what it expected — basically, the sensor is getting confused, not silent. On a Smart that usually shows up as a random stall followed by a clean restart, because the ECU lost track of crank position long enough to cut fuel and spark, then picked it up again.
The cheap-first story is the same as P0335: it's almost always the sensor or its connector before anything else. Reluctor ring damage on the flywheel is the worst case but it's rare, and confirming it needs a scan tool reading live crank-signal data.
One thing worth checking before you spend money: owner reports suggest this code often gets covered under powertrain warranty. If your car is still inside that window, call the dealer before you order a sensor.
Likely causes, cheapest first
- Connector loose or corroded at the sensor. Free to inspect. Heat and oil mist where the CKP lives means pins eventually back out or green up.
- Sensor heat-fatigued and giving noisy signal. The dominant cause once the connector checks out. The sensor still works but the signal isn't clean enough for the ECU to trust at every rpm.
- Wiring chafe along the harness. Less common, but worth a look where the harness routes against metal edges or near exhaust heat.
- Reluctor ring damage on the flywheel. Worst case. A chipped or rust-pitted tooth gives the ECU a tooth-count it can't reconcile. Confirmed only with a live-data scan tool, and the fix means dropping the transmission to access the flywheel.
DIY check steps
- Pull the codes and write down everything stored. P0336 alone, P0335 + P0336 together, or P0336 + P0340 all change the conversation. Pairs that include P0340 push toward a wiring or shared-circuit problem rather than a single bad CKP.
- Visual inspect the connector at the sensor. On the 451 it's at the rear of the block near the bell housing; on the 453 access is tighter. Unplug, look for corrosion, plug back firmly until it clicks.
- Wiggle test if the symptoms come and go. With the engine running, gently flex the connector and harness near the sensor. If the engine cuts out when you move it, you've found a bad pin or chafed wire.
- Replace the sensor. On the 451 it's one bolt and one plug, fifteen minutes if access is good. The 453 takes longer, budget an hour the first time. Clear the code, drive a normal cycle, retest.
When to call a shop
If a clean connector and a new sensor don't clear it, that's scan-tool territory. A Smart-experienced shop with MB Star or Xentry can read live crank-signal data and tell you whether the problem is signal noise (wiring) or a missing tooth on the reluctor (mechanical). Reluctor replacement means dropping the transmission — not DIY for most owners, and the labor bill is enough that a used engine swap is a real comparison at higher mileage. Before any of that, check whether your car is still under powertrain warranty. P0336 is one of the codes that owners have reported getting covered without much pushback.
Related parts & typical prices
| Part | Typical price | Search |
|---|---|---|
| Crankshaft position sensor (451) | $30-120 | Search Google |
| Crankshaft position sensor (453) | $50-180 | Search Google |
| Sensor connector / pigtail repair kit | $10-25 | Search Google |
Prices are rough community-reported ranges, not quotes. Aftermarket vs. genuine Mercedes parts swing the spread; call a Smart-experienced shop for an actual quote.
Manual references
- Service manual on Manualslib — external mirror (we don't host this specific document).
- Browse Smart manuals on smartcarmanuals.com — pick your chassis code section on the home page if a specific manual isn't listed above.
Community references
- Evilution: OBD-II error code reference
- OBD-codes.com: P0336 reference
- SmartCarOfAmerica: P0336 search
Stuck on this one?
SmartDiag-AI runs through the cheap-first checks with you, weighted to community-known patterns for your exact model. The link below pre-fills the code and model.