The padded hose from the PCV valve on the left hand cam cover over to the throttle body plenum, maybe? Often the rubber elbows at each end can leak or become soft and collapse. The PCV valve itself should be replaced every 80k Miles.
I can confirm the Motorcraft part numbers are:
PCV valve: EV-261 (2C5Z-6A666-AA)
Hose to Throttle-body: KCV-240 (2L2Z-6A664-FA)
Unsure of MGR numbers, if thee are any.
David
If you separated the catalyst convertors from the manifold and still had the problem then it may be one of the O2 sensors either side of the cats. I had a similar problem, which continued to get worse until it changed to a missfire, which in turn destroyed one of the cats. I replaced the cats and the failed O2 sensor and all was fine and has been ever since.
Dave Rushfirth
Empty garage where #138 used to be
Posting Permissions
Reply With Quote