 My 2008 Highlander started making a severe sparkknock noise upon cold start. A trip to the dealer and they could not find anything. At 61000 miles the noise is still there and the check engine light comes on code P0017. Trip to dealer and they replace the spool valves for the VVT. problem still there. Dealer pulls engine replaces 4 cams, timing gears, and cam holders. Get car back still making noise. 2 weeks later ck eng lamp on P0017, along with p0301,303,305, and 300. Dealer said it was old codes. I knew better. dealer clears codes. Lamp on again this time p0017 & p0018. I called Toyota customer service. Dealer tells ,e that they cleaned the top eng internal problem has not ret now 85k