I'm at my wit's end with my 2014 Bounder Classic 36H (2013 Ford F53 V10 chassis). The engine cranks over strong but absolutely will not start. I've been chasing this for weeks and I'm really hoping someone can point me in the right direction.
Here's what I know: Forscan is showing cam sensor faults while cranking, even after I replaced the cam sensor. I've got fuel pressure, the crank sensor is new, and there are no stored codes. The tachometer moves during cranking attempts, so I know I'm getting some signal. After crank attempts, there's a strong fuel smell. I've disconnected the battery ground for over 5 minutes to reset any hanging codes.
I'm starting to suspect this might be a wiring harness issue or possibly something with the timing chain. I have a tone generator on the way to check for potential wire breaks. The frustrating part is that everything seems like it should work, but it's like the PCM isn't getting the right timing information.
I really need guidance on the most likely culprits for cam sensor faults on these V10s. What should I be focusing on to get this thing running again?
A Ford F53 V10 that cranks but won't start with cam sensor faults typically indicates wiring harness issues, timing chain problems, or PCM communication failures. Focus on checking the cam sensor wiring circuit and timing synchronization between crank and cam sensors.
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Your 2013 Ford F53 V10 in the Bounder Classic 36H is experiencing a classic cam sensor signal loss issue that's preventing ignition timing, even though you've replaced the sensor itself. Since Forscan is showing a cam sensor fault specifically during cranking, and you're getting fuel smell after cranking attempts, the engine is getting fuel but no spark due to the ECU not receiving proper cam position signals. The fact that you have tach movement during cranking suggests the crank sensor may be working, but without cam sensor input, the PCM can't determine proper timing for fuel injection and ignition. This points directly to a wiring harness problem between the cam sensor and PCM, likely in the connector or along the wire run, rather than the sensors themselves.
The 2013 F53 V10 uses a Hall Effect camshaft position sensor that sends a square wave signal to the PCM to determine cam timing for sequential fuel injection. When this signal is lost or corrupted, the engine will crank but won't fire because the PCM can't synchronize ignition and injection timing. Common failure points include corrosion at the cam sensor connector, broken wires in the harness where it flexes near the engine mount, or damaged pins in the PCM connector.
The cam sensor circuit typically uses three wires: power (usually red/yellow), ground (black), and signal (gray or tan). Since you're parked in a barn, moisture condensation could have caused corrosion at connection points. The F53 chassis is also known for harness chafing issues where the engine harness passes through the firewall area, especially on units that have seen road vibration over the years.
You'll need your tone generator when it arrives, but also gather a digital multimeter, electrical contact cleaner, dielectric grease, and potentially wire matching the original gauge and weatherproof connectors if you find broken conductors. Have your Forscan laptop ready for real-time monitoring during testing. You'll also want a good flashlight and possibly a mirror to inspect the back side of the PCM connector area.
Locate the cam sensor connector - it's typically on the passenger side of the engine near the cam sensor itself. The PCM is mounted behind the dashboard area, and accessing the connector may require removing some panels. Having the service manual wiring diagrams would be ideal, but the tone generator will help you trace the specific wires from sensor to PCM.
Start by disconnecting the cam sensor connector and inspecting both male and female sides for corrosion, bent pins, or moisture. Clean with electrical contact cleaner and check for proper pin tension. With the connector apart, use your multimeter to check continuity from each sensor pin back to the corresponding PCM pin - this is where your tone generator will be invaluable for wire tracing.
Check the power wire first - you should see battery voltage at the sensor connector during cranking (power may only be present during crank on this system). Then verify the ground circuit has less than 0.5 ohms resistance to engine ground. The signal wire is most critical - it should show continuity from sensor to PCM with no continuity breaks when you wiggle the harness along its entire length.
Pay special attention to where the harness passes through the firewall and anywhere it might contact hot engine components or sharp edges. The F53 is notorious for harness damage near the steering box area and where wires route around the engine mount brackets. If you find a break, repair it with proper gauge wire and weatherproof connectors, not just twist and tape.
After any repairs, reconnect everything and use Forscan to monitor cam sensor signal in real-time while cranking. You should see a clean square wave signal that doesn't drop out (requires oscilloscope for proper signal analysis). Clear any stored codes and test start the engine.
If your tone generator and continuity testing reveals the wiring harness is intact, the problem likely lies in the PCM connector itself or internal PCM circuitry. PCM connector pins can become loose or corroded, especially on 10+ year old chassis that have experienced temperature cycling and vibration. This requires careful inspection of the PCM connector pins and potentially specialized tools to repair connector issues.
Should the wiring check out completely and the PCM connector appear sound, you may be looking at an internal PCM failure in the cam sensor input circuit. This would require PCM replacement or professional-level diagnostics with oscilloscope testing to verify signal integrity. Given the cost of a replacement PCM (typically $800-1200 for this application), professional diagnosis becomes cost-effective at this point to avoid unnecessary parts replacement.
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