Fixing Ford misfires, rattles and no-starts
Some 2010 Explorer, Mountaineer Explorer Sport Trac vehicles equipped with the 4.0L engine and Mustang vehicles equipped with the 4.0L engine with manual transmission may exhibit problems such as engine rattle noise, MIL on with code P0340, misfire codes, lack of power, rough running or no-start conditions. This affects vehicles with engine build dates from 5-28-2009 to 6-30-2009.
If the engine build date falls within this range:
If the engine exhibits a rattle noise that gets worse when in drive. Between idle and 1,100 rpm (with no DTCs stored in the PCM), use a stethoscope and check for rattle noise near the front of the engine block cradle. If rattle noise is detected, remove the cylinder block cradle. Replace the balance shaft sprocket using Kit A – Timing Gear Set balance Shaft. While servicing the balance shaft sprocket, determine if the balance shaft assembly spins freely. If it does not spin freely, replace the balance shaft.
If the vehicle has DTC P0340 stored in the PCM and has misfire codes, lacks power and/or runs rough, remove all camshaft roller followers. Remove all spark plugs. Perform a cylinder leakage test on all cylinders. If leakage exceeds 20% or less on all cylinders, remove the block cradle and replace the balance shaft sprocket and balance shaft drive chain. If the balance shaft does not spin freely, replace the balance shaft as well. Be sure to inspect all timing components for wear/damage.
If the engine cranks but does not start and DTC P0340 is stored, use a scan tool to monitor the rpm signal during engine cranking. If the rpm signal is present and DTC P0340 is stored in the PCM, using IDS, follow the prompts in the scan tool and perform a relative compression test. If the relative compression test fails, Ford recommends replacing the engine long-block assembly.