FAQ
TL;DR: Peugeot 206 1.4 HDI crank–no‑start with P0337 can show 350 bar rail pressure yet “no injection control.” Scope the crank sensor, verify wiring, then check timing. [Elektroda, LEŚNY, post #16736542]
Why it matters: This FAQ helps DIYers and techs quickly isolate crank/no-start faults, especially P0337-related issues on PSA 1.4 HDI engines.
Quick Facts
- DTC P0337 = incorrect crankshaft speed sensor signal on this case vehicle. [Elektroda, LEŚNY, post #16740464]
- During cranking, approx. 350 bar rail pressure was observed without injector actuation. [Elektroda, LEŚNY, post #16736542]
- Experts in-thread advised a timing check as a primary step. [Elektroda, kortyleski, post #16740600]
- Confirmed fix in-thread: shifted timing corrected; engine started after reset. [Elektroda, LEŚNY, post #16749517]
- Edge case: two fan-box relays by the radiator; burnt connector/wire prevented start until repaired. [Elektroda, ALIBABA I, post #16740723]
What does code P0337 mean on a Peugeot 206 1.4 HDI?
P0337 indicates the ECU sees an incorrect or weak signal from the crankshaft speed sensor. On the thread car, the code was present after the sensor was replaced and wiring continuity was confirmed, pointing diagnosis toward signal quality and timing rather than simple open circuit faults. [Elektroda, LEŚNY, post #16740464]
Can I have good rail pressure but still no start?
Yes. The thread shows about 350 bar during cranking while injectors were not commanded. That combination suggests the ECU withholds injection because it cannot trust the crank signal or timing correlation. “No injection control” was the symptom despite fuel supply. [Elektroda, LEŚNY, post #16736542]
How do I check the crankshaft sensor signal with basic tools?
Use an oscilloscope at the sensor or ECU pins to view pulse trains while cranking. Confirm consistent amplitude and tooth pattern. The poster captured usable pulses yet still had a fault, which directed attention to timing alignment and correlation checks. [Elektroda, LEŚNY, post #16736542]
Where should I probe the wiring—at the sensor or the ECU?
Probe at both ends. Peugeot looms use numerical markings rather than relying on colors, so identify wires by numbers at the ECU connector. This ensures you verify the exact signal and return paths the ECU sees. [Elektroda, piotrekwoj1, post #16739409]
Could incorrect timing cause a P0337 and no start?
Yes. The documented fix was correcting shifted timing; after replacement and re‑setting, the engine started immediately. Loss of phase correlation can make the ECU suppress injection even with pressure present. [Elektroda, LEŚNY, post #16749517]
How do I check for a slipped crank pulley key (wedge)?
Remove the crank pulley and inspect the keyway and key. A damaged or sheared key can offset timing marks while the belt looks aligned. “I had a topic with a wedge” highlights this failure mode on similar engines. [Elektroda, szymitsu21, post #16740638]
Why don’t injectors click or light a test bulb during crank?
If the ECU flags a crank signal fault, it can inhibit injector drive. In the case, an H4 bulb on an injector line did not light, confirming no current to the solenoid despite fuel pressure. [Elektroda, LEŚNY, post #16736542]
The engine starts on spray but dies—what does that indicate?
Starting on starting fluid (“poster”) shows base compression and mechanical timing are close enough to fire, but the ECU still withholds fuel due to signal or correlation errors. Focus on the crank circuit and timing sync. [Elektroda, LEŚNY, post #16736542]
Could radiator-area relays stop the car from starting?
Yes, an edge case showed two relays in the fan-box near the radiator. A burnt wire and corroded connector prevented starting; repairing the connector and relay restored normal operation. [Elektroda, ALIBABA I, post #16740723]
Can a faulty instrument cluster really block starting?
It can on related PSA/Ford 1.4 HDI implementations. One user’s Fiesta 1.4 HDI needed cluster repair/replacement after repeated solder failures caused crank-but-no-start. Consider this if common causes test good. [Elektroda, master1991, post #16729977]
What quick 3-step plan should I follow before swapping parts?
- Scope crank sensor at ECU pins; confirm clean pulses while cranking.
- Verify rail pressure during crank; note that ~350 bar may still not start.
- Check injector command with a test bulb; absence suggests ECU inhibition.
“Scope, pressure, command” narrows the fault fast. [Elektroda, LEŚNY, post #16736542]
Is ECU failure likely here?
Less likely than timing or signal issues in this thread. With pulses present and P0337 logged, members advised mechanical timing checks first; the final fix confirmed timing shift, not an ECU fault. [Elektroda, LEŚNY, post #16749517]
Should I rely on wire colors during diagnostics?
No. Peugeot uses numerical identifiers on harness conductors. Trace by number from sensor to ECU for accurate continuity and signal verification. This avoids color-code misreads after loom repairs. [Elektroda, piotrekwoj1, post #16739409]
What was the final outcome in the thread case?
The owner corrected shifted timing, re‑set the timing, and the car started normally. This closed the case and validated the advice to inspect timing early in P0337 no-starts. [Elektroda, LEŚNY, post #16749517]
