The Secondary valve actuator is known to go bad after 50,000miles because of heat being trapped underneath the vanity cover. I am having the same problem that you were having in the past. I was instructed to take the cover off to reduce heat and it didnt change the way it operated. No one i have talked to has had any other suggestions. Best thing to do is go and buy a new one the part number is written on the bottom IMRC box. THey cost about $150.00 online, or if you are lucky you can find a adjustable actuator for about $300.00 That will allow you to set what Rpm you want to ingage it at.
