Yes it sounds like a vacuum leak since the problem started after the intake manifold replacement.
The MAP sensor must be connected to manifold vacuum, and a non functioning EGR may cause an error code.
The job of the EGR valve is to lower combustion temperature to prevent formation of oxides of nitrogen.
Is this intake an aftermarket unit or a Honda part?
You need to fix this ASAP as a vacuum leak will cause the engine to run lean and possibly burn a piston.
Sunday, August 30th, 2009 AT 9:01 AM