Cold start chain rattle

[lamrith]

Well I think the clock is ticking on my baby.  I have been remote start for a while now so no idea when it started, but I did a cold start 2 days ago when I was next to the car and heard what can only be described as a chain riding on metal sound right when it fired.  Made my heart sink, I am pretty sure that means it needs timing done?  Is it the guides that are failing usually? or chain stretch? 


Not looking forward to the bill, but it is not something I am able to do myself at this time with other cars already down and in garage.  I may just have them replace the water pump while it is open as I seem to be seeing a number of people with pumps failing lately in other groups.  Any items I should be looking to make sure is on the repair while it is open?

 

[Admin]

On the transverse its usually timing chain stretch that does it.. but doesn't mean the guides arent worn out either..

Besides the typical timing chain service, I would make sure the water pump is serviced as well since its cracked open. I would also see if they could do a drain/fill on the PTU while its being worked on.

 

[lamrith]

On the transverse its usually timing chain stretch that does it.. but doesn't mean the guides arent worn out either..

Besides the typical timing chain service, I would make sure the water pump is serviced as well since its cracked open. I would also see if they could do a drain/fill on the PTU while its being worked on.

Def plan on water pump for sure. 


PTU I have a '13 so will just do that myself. Rather not pay for it when I have everything at home for it. I did it when I got the car and it was not that difficult to do while under the car for an oil change.

 

[SHOdded]

make sure to get cam holding tools, a set of slim wrenches, and NOT go gorilla on torquing down the main/timing cover while installing it.  the cover is usually the most aggravating part of the install due to the tight space and the limited time you have before the sealant sets.

how long does the rattle last?  do you have a lot of accessories come on at remote start? when was the battery last replaced/tested? crank speed can make a difference as it will affect the speed with which oil gets to the timing components. be sure to check and replace the VCT solenoids if you do proceed with the job.  if you find the battery is draining, you might think about enabling Dark Mode to save drawdown while the car is off. this was discovered by a fellow member from Alaska.

high moly oils are also helpful in this regard.  I too am experiencing brief startup rattle on my 2007 3.5L NA, and using Driven FR20 has significantly reduced the duration, eliminated it even on some startups.  coming up on 1500 miles on it now.  don't skip the oil changes, easy to do during these times.

a reference to get you started:
The Role Additive Chemistry Plays in Increasing and Decreasing Timing Chain Wear</a>


ultimately, replacement is the right path, BUT then you have to take a few small steps to prevent the situation from developing again