I installed a new EGR valve, cleaned the intake manifold including the EGR port. Put SeaFoam in the gas, oil, and a little thru the vacume lines. I'm not getting any of the P0300 thru P0306 or P0401 DTCs anymore. BUT I'm still getting the P1399 DTC w/ a mild skip under load. The plugs are new Bosch 4428 +4 PLatinums What else could be causing the P1399? Or do I just need to let the SeaFoam work its" way thru the systems?
have the same problem?
Monday, April 4th, 2011 AT 12:45 PM