P13B6

What the Code Means

Code P13B6 sets when the reference angle difference between the crankshaft and the exhaust camshaft falls outside the allowed value. Under normal conditions the DME continuously compares the position of both shafts: their relative angles must stay within a tightly specified tolerance. When synchronization is lost, the control unit receives incorrect data on exhaust camshaft position and can no longer manage valve timing correctly.

Typical causes are timing chain problems (stretch, a failed tensioner), failed shaft position sensors, or damaged wiring and connectors.

Symptoms

Indication:

• Check Engine Light is on

Engine operation:

• reduced power
• misfires
• increased fuel consumption
• hard starting

Diagnosis and Repair

1. Read codes and live data with ISTA or INPA.
2. Check timing chain tension and stretch. If the chain is stretched, replace it — part number 11317548389.
3. Check the camshaft position sensor (12147522357) and the crankshaft position sensor (12147539175); replace any that are faulty.
4. Inspect wiring and connectors for damage, corrosion, and poor contact.
5. If none of the checks above finds the cause, replace the ECM.

Secondary Problems

Ignoring P13B6 is critical in its consequences:

• timing chain jump, where piston-to-valve contact is possible and catastrophic engine failure follows — the most expensive repair scenario;
• misfires damage the catalytic converters, which then need replacement.

Don't put off diagnosis with this code: the interval between “angle mismatch” and mechanical engine destruction can be short.