I also have a intermittant check engine light w/ EGR code (P401). I see there are many very helpful postings regarding the EGR/VSV, however I don't have any mechanical skills so my question is what is a worst-case repair cost I would expect? I would assume that the problem is either with the EGR or the VSV and a good & honest mechanic should figure out which one to replace or if I'm lucky, just clean EGR. It seems the possibilities are:
a. diagnose/clean EGR b. diagnose/replace EGR c. diagnose/replace VSV d. diagnose/replace VSV & EGR
with "d." being unlikely if the mechanic is good/honest.
Any estimates on what a typical mechanic would charge for a. - .d would be greatly appreciated.