Jaguar XF 5.0L P0506 - Rough Idle and Stalling at Stop Lights

Question

My 2011 Jaguar XF is struggling to maintain a steady idle after warming up. When I come to a complete stop, the RPMs dip below 500 and sometimes the engine just cuts out completely. The Check Engine Light is on and my scanner shows a persistent P0506 code.

Kevin Tran · Accepted Answer

The issue was a heavily fouled throttle body and a small vacuum leak at the brake booster line. I removed the throttle body and cleaned it thoroughly with specialized cleaner, then performed a 'Throttle Position Sensor Adaptation' reset using an SDD tool. I also replaced the plastic vacuum connector (Part #C2Z28220) which was cracked. The car now idles perfectly at 650 RPM and the code has not returned after 300 miles of driving.

Carlos Diaz · Answer

It might be an electrical issue with the Throttle Actuator Control. Try performing a hard reset by disconnecting the battery cables and touching them together for 30 seconds to clear the learned adaptations.

backyard_bart · Answer

You should check the throttle body for carbon buildup. On these AJ133 engines, even a small amount of residue around the butterfly valve can restrict enough airflow to cause the P0506 code.

turbo_tony · Answer

Have you looked at the PCV valves? These Jaguars are known for the PCV diaphragms tearing, which messes with the idle trim. Listen for a whistling sound near the valve covers while it is idling.

Jaguar XF 5.0L P0506 - Rough Idle and Stalling at Stop Lights

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