2007-2014 Cadillac Escalade vehicles equipped with a 6.2L engine may exhibit a rough idle and rough running engine, with DTC P0171 and/or P0174 stored (fuel trim system lean, bank 1 or 2).
Inspect the PCV tube for a vacuum leak on the left side of the engine. The engine cover can cause a rub-through on the PCV tube located at the left rear of the intake manifold, just above the fuel line connection. If this is the case, replace the PCV dirty air tube and cover it with a conduit to protect against repeat damage. Reset the idle and perform a fuel trim retest.
After replacing the air tube, cover it with a conduit to protect the tube.
Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety ofspecialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.
