Engine Reliability
I found it hard to believe given i was told mercedes engines were essentially bulletproof?
Everyone's thoughts / experiences?
I found it hard to believe given i was told mercedes engines were essentially bulletproof?
Everyone's thoughts / experiences?
There have been issues with the older 63's that have the M156 (the old NA 6.2L), including a class-action lawsuit against MB/AMG.
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Long story short, the car out of the factory is very reliable. Once you start adding mods, it's pay to play and the ball is in your court.




1. MAP sensor located on one intercooler needed replacement.
2. Wastegate line off turbo replaced (kinked)
3. Boost hose directly off the passenger side turbo cracked/split, replaced with new rubber boost hose.
I attribute Texas heat to most of those failures - as they all happened within a month when the weather got very hot. Only mods were Dinan tune and 305 rear tires.
Internally, this engine is extremely stout and can handle 700-800+ crank HP. It’s all the electronics, sensors, etc. that I’d be concerned about because they don’t generally fail until they’ve aged (typically after warranty is up). Luckily these were all easy dealership fixes with no out-of-pocket expenses.
1. MAP sensor located on one intercooler needed replacement.
2. Wastegate line off turbo replaced (kinked)
3. Boost hose directly off the passenger side turbo cracked/split, replaced with new rubber boost hose.
I attribute Texas heat to most of those failures - as they all happened within a month when the weather got very hot. Only mods were Dinan tune and 305 rear tires.
Internally, this engine is extremely stout and can handle 700-800+ crank HP. It’s all the electronics, sensors, etc. that I’d be concerned about because they don’t generally fail until they’ve aged (typically after warranty is up). Luckily these were all easy dealership fixes with no out-of-pocket expenses.
51K miles on my car, with ~40K of those run with a Eurocharged tune. All of it in TX weather. The car was never abused, but it wasn't babied either. Never had any engine issues other than the MAP sensor and a couple misfires (eventually traced vapor lock from running winter-blend fuel in 80F+ weather).




It isn't that parts break. It's that the location can be a challenge comparrd to the M156 and M157.




Looking over my service sheet, it looks like the tech had the intercooler out to just to replace the torn boost hose: "replaced waste gate vacuum line. during repair found passenger side turbo boost charge air hose to have a crack. partially removed right side charge air intercooler. replaced right side charge air boost hose. performed road test. found vehicle to operate as designed."
I can see why when I bought a pair of used turbos, it came with a set of boost hoses still attached with the hoses cut off at the ends... someone didn't want to bother...





