With nearly 150,000 0n my 2007 Expy the VVT SPROCKETS (cam phasers?) have begun to seriously worry me. They've made the notorious tick-clicky noise at idle between 900 - 1200 rpm for several years now, never loud enough that it captured my attention enough to cause concern.
A couple weeks ago while in a drive through I noticed the noise was "surging"...that is, it would grow louder then quieter. At first I thought it was spark knock/dieseling. I drove off into the parking lot, but it would not do it again.
A couple weeks later same deal. Just randomly gets louder then quieter while in drive at a stop. Easier to hear when at a drive through or next to a building wall where the sound bounces back. I have been planning to replace the whole timing assembly this WINTER. I simply can not be out in this heat...not by choice.
In my research, it seems every mechanic has their own idea of how to repair this problem. My #1 concern, based on what I've researched, is that the phasers can & DO break apart causing catastrophic engine damage that requires a new or rebuilt engine. I've read replacing the two VVT Solenoids may solves the issue if the sprockets are not too far worn. I plan to replace these anyway as I understand there has been an upgrade...something to do with the solenoids allowing more oil to reach the sprockets?
The valve covers need to be removed to replace the solenoids. NOW, here is my dilemma: I see where quite a few mechanics replace JUST the sprockets leaving the rest of the original timing components in play...chain, tensioners, etc. I'm old school. YEARS ago owned & operated my own auto repair shop. I would NEVER replace one component of a multi-component assembly such as a timing assembly simply because of how everything all wears together...installing a new part that comes into contact with a worn old part could prematurely wear/ruin the new part...or the other way around, or BOTH.
With the newer engines/timing designs like on my 5.4 Trition, is it common practice to replace JUST the VVT Sprockets and leave the rest original? If so, is it recommended? I just have a hard time with this concept. However, IF it is something that is done with regularity and causes no adverse issues I may opt to replace just the sprockets & solenoids at this time.
ALSO: I see DORMAN brand sprockets for $105 on Parts Geek. Haven't checked Rock Auto yet. I was searching ebay & saw whole timing kits WITH both solenoids for my motor...$288.00(minus any gasket sets/seals) but no brand name on the kits. I'm simply assuming those are junk....as in "you get what you pay for" IF your lucky!
FWIW, I bought my expy new & have taken great care of it. I plan to hang on to this one for the duration. Sorry, I realize this post is pretty long. I went back & shortened it a good bit.
A couple weeks ago while in a drive through I noticed the noise was "surging"...that is, it would grow louder then quieter. At first I thought it was spark knock/dieseling. I drove off into the parking lot, but it would not do it again.
A couple weeks later same deal. Just randomly gets louder then quieter while in drive at a stop. Easier to hear when at a drive through or next to a building wall where the sound bounces back. I have been planning to replace the whole timing assembly this WINTER. I simply can not be out in this heat...not by choice.
In my research, it seems every mechanic has their own idea of how to repair this problem. My #1 concern, based on what I've researched, is that the phasers can & DO break apart causing catastrophic engine damage that requires a new or rebuilt engine. I've read replacing the two VVT Solenoids may solves the issue if the sprockets are not too far worn. I plan to replace these anyway as I understand there has been an upgrade...something to do with the solenoids allowing more oil to reach the sprockets?
The valve covers need to be removed to replace the solenoids. NOW, here is my dilemma: I see where quite a few mechanics replace JUST the sprockets leaving the rest of the original timing components in play...chain, tensioners, etc. I'm old school. YEARS ago owned & operated my own auto repair shop. I would NEVER replace one component of a multi-component assembly such as a timing assembly simply because of how everything all wears together...installing a new part that comes into contact with a worn old part could prematurely wear/ruin the new part...or the other way around, or BOTH.
With the newer engines/timing designs like on my 5.4 Trition, is it common practice to replace JUST the VVT Sprockets and leave the rest original? If so, is it recommended? I just have a hard time with this concept. However, IF it is something that is done with regularity and causes no adverse issues I may opt to replace just the sprockets & solenoids at this time.
ALSO: I see DORMAN brand sprockets for $105 on Parts Geek. Haven't checked Rock Auto yet. I was searching ebay & saw whole timing kits WITH both solenoids for my motor...$288.00(minus any gasket sets/seals) but no brand name on the kits. I'm simply assuming those are junk....as in "you get what you pay for" IF your lucky!
FWIW, I bought my expy new & have taken great care of it. I plan to hang on to this one for the duration. Sorry, I realize this post is pretty long. I went back & shortened it a good bit.
