Timing Actuoator. What is this all about?
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2004 Scion xA
Question: 170,000 miles. Engine starting to make a noise. Am told it is the Variable valve
Answer #1ziptie12 July 12, 2012, 13:55Master
It a hydraulically operated cam gear that advances or retards timing based on various inputs from other sensors.It's to maximize both power,fuel economy and emissions.(most people just like it for the boost in performance , hey!. why not? When not operating properly it can make a very harsh rattle on start-up 1-2 seconds in some cases.May also cause the check engine light to come on if the duration of the faulty cam timing readings last long enough for the PCM to detect.
ReplyNobleJ, July 12, 2012, 18:58Rookie
What is the average cost to replace it?
Is it necessary to replace?
Will it cause further damage if not replaced?
Replyziptie12, July 12, 2012, 20:52Master
as far as cost, you'll have to check locally or use the repairpal app for estimate.It is necessary for proper engine performance and will slowly do damage to your emissions system most likely.