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Rough warm start!! Timing Chain issue?

500 Views 5 Replies 2 Participants Last post by  Kroniqphelps
Hello all,I want to apologize in advance for the length of this post but I figured I give u guys as much info as possible so I am experiencing a rough shaky start on my W212. Before buying this car for a little under market value at 94k on odometer (I now have 116k) , I did extensive research on the engine numbers dealing with that issue and I found an engine that was made after the “fixes”. The production date was May 2013 and engine 30 466xxx which already had updated check valves and tensioners. The problem is that I just started experiencing a rough shaky warm start after sitting for at least 5-10 mins. It shakes like it’s about to stall out along with some loud rattling for about 3-4 seconds. In the morning during cold start, I get the normal engine noise but I don’t NEVER once got the timing chain rattle and engine shake/ stalling feeling. Seems to only happen when engine is cooling down and not COMPLETELY COLD
After reading, I saw that there are some cases where the issues still happen after the “fix” production dates. I recently did an oil change which was about 1100 highway miles overdue and the noise is still there. I also read that pressing the brake pedal a few times and holding it during starting helps reduce the rattling and it does but does solve the problem. I am thinking of purchasing an extended warranty to have the issue fixed.
I want to pull the timing covers myself but the whole process of throwing parts at it isn’t something I wanna do. I wanna just pinpoint the problem and get it fixed but I know I can’t do cam adjusters on my own. So my question is do I purchase the Endurance warranty (I think that’s the best one I saw so far) before the CEL comes on and have them deal with the breakdown and fix? I posted a picture of what’s covered under their sample contract and it shows timing chain and gear and camshaft so it seems they would cover everything dealing with the timing right? ORRR do I start with removing the timing covers and doing some work myself?
Sorry again for the lengthy post and thanks in advance guys. I will try to get a video up of the noise


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Before buying the Endurance warranty, I would be very specific in asking whether the faulty camshaft adjusters, and any additional timing system repairs are covered, if there is no CEL. I bet the answer is no. I was quoted $10,000 for the full “Monty” by the dealer: all four cam adjusters, new timing chains, all new chain rails, new tensioners, four new camshafts (I believe).
I did the job myself. Only needed one new cam adjuster. I did replace the secondary chain tensioners, and my engine did not have the check valves installed, so I did check valves as well. I did the entire repair through the front covers only, with rear vacuum pump removal (bank 2) in order to access internal #60 torx at rear of camshaft. This enabled me to use a helper to counter hold during loosening and tightening procedures necessary to replace defective camshaft adjuster (bank2/intake) in my case. I did not remove the valve covers. Car is perfect now. No cold start rattle, idle is smooth, acceleration is fantastic , gas mileage is fantastic. Engine is absolutely still at idle. No codes.
Yea I’m thinking of just taking the time off to just work on this. I would be very meticulous and slow in the procedure as it’s my first time even attempting something this big. I’m a quick learner and been watching these videos on the procedure countless times but you made it seem so much simpler than the videos explain. I would have to get through diagnosing the entire thing myself and then going from there. Should check valves be faulty if this engine should’ve gotten all the necessary timing upgrades? I’m kinda tryna prepare what I’m going to be doing when I get in there. I kinda want to order everything and return what I won’t use because I don’t want to continually remove the intake.

Wanted to add this earlier but had to stop with the essay: I have also been using 89’ gas because it’s fr33 but since yesterday I have been using ‘93 again after the fresh oil change to see if this is gonna improve the start up noise and I can honestly say that there has been a drastic decrease of the rattle/stalling feeling In less than 24 hours. I don’t know if the use of ‘89 had an affect that bad but I’m gonna keep monitoring it everytime I start it the next few days.

But yea back to the drawing board. Im gonna just order some intake gaskets to replace once I lift it up so I can check the timing and then order the kit or cam adjuster depending on what I find
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This is what it sounds like after a drive to work and letting it sit for a few hours. In the morning, it doesn’t sound this bad.
Could it be possible that the chain tensioner could just be stuck or something or is the code bound to come?
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