The Lambda unit on my D is dead. I am guessing that this could be the cause of a host of problems with my car -- lack of power, frequency valve not buzzing and flunking Arizona's emission test. Would this unit be responsible for all of the items I have just listed and would the dead lambda unit cause any other problems I should be aware of ? Since my car has always driven like this since I have owned it, my guess is that it will be a big change once I get this thing fixed. Also, is this something that can be repaired or just replaced as I believe it is a few hundred bucks for a new one. Thanks for the help. Mark