Ford Repair Questions? Ask a Mechanic for Answers ASAP
This is very common concern, you will need upper intake manifold seals and Bolts, there are seals around the bolts! Tsb is below.
This article supersedes TSB 05-17-3 to update the vehicle model years and issue.
Some 2001-2003 F-150, 2004 F-150 Heritage and 2001-2003 E-150/250 vehicles equipped with a 4.2L engine may exhibit the malfunction indicator lamp (MIL) on with diagnostic trouble codes (DTCs) P1131 and/or P1151 (system too lean bank 1 or 2). This condition may be due to leaking isolator bolts/port gaskets in the upper-to-lower intake manifold mounting area. This condition is sometimes intermittent and may not be apparent on a warmed-up engine.
Refer to the following Service Procedure.