AMG80138

Good day to all:

Hoping to get some advice;
2012 CLS63 AMG
Car was running fine, but at times starting it would take 3 or 4 times longer (as far as cranking over). then at times fired on the first turn. (CEL P0018) it would at times lose power at high end, but idle was smooth and ran without issue. I took it to the MB dealer and they said it "spun the timing plate on the camshaft and that needed to be replaced. I bit the bullet ($4,000) and had the camshaft replaced, they called me a few days after and said it now had a fairly bad misfire at idle, however, that it would go away after 3,000 RPM and that the timing was fine now, but misfire was not going away. Next day after trying to resolve the misfire they called me and said "oh, you also have a bent valve on #7. I informed them that it ran fine prior to coming in there and never had any misfire, they said it was bent just enough that when they took the original camshaft out it, that valve now will not seat correctly. And I would need to replace the head entirely with new valves ($9,500.00 Parts and labor)) because the engine must be pulled to remove head. Would the valve have been damaged by removing and replacing the old camshaft? As stated before, never a misfire and ran fine, timing did seem off at times and CEL was constantly coming on. Tech said he was so frustrated that he removed and replaced the CAM 3 times before determining the valve was bent with a leak down test. Any advice, insight would be very much appreciated. Thank you!

Also, if a valve is bent, would that require a NEW head from MB at a cost of over 5K? Wouldn't you be able to replace just the bent valve?

haist82

Valve can be replaced, no need to replace the whole head.

AMG80138

Thanks for the response, do you know if the engine has to be pulled to get the head off? 2012 CLS 63 M157

haist82

Im no expert, but i dont see why you need to pull the engine to get to the heads, they are on top of the engine!

haist82

I would def. get a second opinion from some 3rd party independent mechanic shop.
Good luck!

AMG80138

I just looked, there is literally no room to pull he head off, the engine is very tightly fitted in, the heads are angled at such a degree that there is no way to remove them with the engine intact, so I can unfortunately see why they need to pull the engine. Not the news I wanted to hear

Celicasaur

...spun the timing plate on the camshaft?? I've never heard of a timing plate on a camshaft on any engine. Camshafts usually have a series of metal markers which the cam sensor (essentially a glorified magnet) keeps track of. The crankshaft is the one which has a timing plate...how strange. I need to brush up on my M156 knowledge if this is all true.......

As for the valve, yes it's possible to remove the cylinder head of the side that has the bad valve. However it's a PITA due to space, hence why they want to remove the whole engine. This sucks for you man....sounds like you're being given a raw deal here

To bend a valve, something needed to have been off with the physical timing of the engine, surely....I dunno, this just sounds odd. I hope it turns out well for you buddy. You might have more insight from members on the W204 C63 forum, but they can be a bit of an excitable bunch at times, so bring your flame-suit just in case.

hyperion667

What a shi**y problem, I'm also a 2012 owner and just started driving it daily too..........hope this doesn't happen to me. Please keep up updated as to the progress, and many thanx for sharing.