ML 270 - engine running rough

[ml270n]

Hi All
I recently had the ML serviced and the diesel engine was sounding like a humming bird with the turbo wistle in back.

I then had some problems with PS which wasn't topped up. That was all sorted after posting "wrong steering oil" thread. Since the engine feels very rough especially when accelerating. The engine also feels very tight when reving it up. Diesel clatter also seems louder even when warmed up.

This is gone so bad that I don't even enjoy driving it. There is no loss in power just feels rough and sounds load.

Any ideas? please help.
Thanks

 

[MB TECH WARRINGTON]

Hi All
I recently had the ML serviced and the diesel engine was sounding like a humming bird with the turbo wistle in back.

I then had some problems with PS which wasn't topped up. That was all sorted after posting "wrong steering oil" thread. Since the engine feels very rough especially when accelerating. The engine also feels very tight when reving it up. Diesel clatter also seems louder even when warmed up.

This is gone so bad that I don't even enjoy driving it. There is no loss in power just feels rough and sounds load.

Any ideas? please help.
Thanks

was the correct , and good quality oil used??

 

[oigle]

Dare I suggest that you have the dreaded engine mount problem that I have been writing about recently? Might have coincidentally arrived along with your other problems which can confuse the issue.
If you do look at mounts, do the drivers side one first - it is nearly always the culprit.

 

[ml270n]

Hi all
Yes I used the expensive oil and so far so good. I am keeping an extra bottle just in case.

Thanks, I will check the mounts, but just some observation - normally when a diesel engine just starts up it feels rough and tight until properly warmed up. Mine just stays rough even when warm

 

[oigle]

Hi all
Yes I used the expensive oil and so far so good. I am keeping an extra bottle just in case.

Thanks, I will check the mounts, but just some observation - normally when a diesel engine just starts up it feels rough and tight until properly warmed up. Mine just stays rough even when warm

When the mount dies, the vibration and noise will intrude when hot or cold (worse when cold), particularly under any load and most noticeably around 1800 - 2000rpm. Visually inspecting the mount is not easy. Even if you remove it, unless it has really collapsed, you can't tell if there is a problem with it. Only way to find out is to replace it.

 

[MB TECH WARRINGTON]

Hi all
Yes I used the expensive oil and so far so good. I am keeping an extra bottle just in case.

Thanks, I will check the mounts, but just some observation - normally when a diesel engine just starts up it feels rough and tight until properly warmed up. Mine just stays rough even when warm

some of the 270 engines i feel sound a bit more agricultural than others, it may just be the norm, i feel the 270 are far more harsh than the 220 or 320, just what ive concluded, i maybe wrong, but thats my thoughts, prob not what you wanted to hear,,,

just a thought, remove your engine cover and check your injectors have no blow past, this can cause chuffing type noises and makes them sound different,

with noises its hard for us to guage from a description, without hearing the engine its really hard to diagnose,
id recommend taking to a reputable specialist who works on the cars/engines every day and get a second opinion from them,, keep us informed,

 

[Xtractorfan]

Something ive found with my own car, using supermarket fuels and especially city diesel does make it run noisier and harsh.. Oh and one other thing did you use the genuine Mb fuel filter..some of the other brands have much finer filtration and cause virtual fuel starvation..making the engine work harder and noisier

 

[Mark A]

just a thought, remove your engine cover and check your injectors have no blow past, this can cause chuffing type noises and makes them sound different,

Deffo worth a look. I had this problem on my 02 ML-270 last year, and because it hadn't been picked up for so long, it was a right pig to get sorted (lots of time to get the carbon deposits off to enable a good seat again).