3000 rpm limit after oil changing!

[nashu]

hello! Help needed!

I have a MB C220 CDI, 12/2001(S203) model and a week ago I changed the oil. Before changing I have used ARAL 5W-40 and then I put Mobil 1, 10W-40 and I've reset the service interval. During first engine start with the new oil a heard that the engine sound was not normal and after first 5 km my engine was limited at 3000 rpm.

The next day I changed again the oil (after 30 km with the 10W-40 oil) and this time I use BP Visco 7000, 0W-40 thinking that this BP oil is better because is fully syntetic. I have, also, reset the service interval.

But I have problems with this oil,too. The engine sounds good until 2000 - 2500 rpm and after this it sounds like it is cold (2500- 3500 rpm). If I am in 4th gear or higher the limit at 3000 rpm still comes.The turbo,also, works fine until 2500 rpm and then I don't know what happens with it because the cold engine sounds starts!

My question is if I must change again the oil with ARAL 5W-40 (which works before changing the oil) or if I have another problems because of that 30 km driving with Mobil 1 , 10W-40.

 

[slk280rc]

hello! Help needed!

I have a MB C220 CDI, 12/2001(S203) model and a week ago I changed the oil. Before changing I have used ARAL 5W-40 and then I put Mobil 1, 10W-40 and I've reset the service interval. During first engine start with the new oil a heard that the engine sound was not normal and after first 5 km my engine was limited at 3000 rpm.

The next day I changed again the oil (after 30 km with the 10W-40 oil) and this time I use BP Visco 7000, 0W-40 thinking that this BP oil is better because is fully syntetic. I have, also, reset the service interval.

But I have problems with this oil,too. The engine sounds good until 2000 - 2500 rpm and after this it sounds like it is cold (2500- 3500 rpm). If I am in 4th gear or higher the limit at 3000 rpm still comes.The turbo,also, works fine until 2500 rpm and then I don't know what happens with it because the cold engine sounds starts!

My question is if I must change again the oil with ARAL 5W-40 (which works before changing the oil) or if I have another problems because of that 30 km driving with Mobil 1 , 10W-40.

I think the unusual noise and the subsequent 3000rpm limit, are indirectly related to your oil change. Perhaps you knocked an electrical connection off, or something similar?

The 3000rpm limit suggests the ECU has put the engine into a safe mode. You will have to have the fault codes read and cleared, to find out what it is and return to normal operation. And, of course, you'd need to fix the fault that's been introduced too!

I am pretty sure you won't need to change the oil again, so long as the current stuff has the right rating. The slight viscosity difference between 10W40, 5W40 and 0W40 should not be anything to worry about.

 

[nashu]

I want to add more information about what happen with the engine...
The limit to 3000rpm comes only when I drive more than 2500 rpm for about few seconds. In other words the limit comes only when I stress the engine not every time.

For example yesterday I drove 300 km under the 2000 rpm. And when I arrive home I tested if the engine have enterred in safe mode, and it doesn't.
The engine doesn't enter in safe mode when I drive under 2000 rpm.

The limit at 3000rpm is resetted when I stop the engine and it appears only if I drive for few seconds at more then 2500 rpm. I don't understand it!

And the oil level is ok only after 1 min from engine stop.

It is possible that oil viscosity to be too low when the oil is hot?
And the engine runs without oil at more than 2500 rpm?

and after 2000 - 2500 rpm I hear a sound like the oil is too low or like the engine is cold...(I have added 6.5 l of oil during change)

I will check the ECU for errors but I don't think is due to some wire disconnection.

Please help because I'm affraid not to damage the engine if the oil is not good!

 

[nashu]

One more question: Does The fault code remain in ECU if the fault doesn't exists anymore? Or it is cleared at engine stop?

 

[MondeoMan]

As I've said before, this isn't due to oil. Without wishing to sound rude, I don't think you have the mechanical knowledge necessary for any DIY work, taking it to a dealer or specialist would be your best bet.

 

[television]

One more question: Does The fault code remain in ECU if the fault doesn't exists anymore? Or it is cleared at engine stop?

The fault codes remain until cleared.

Malcolm

 

[severn]

I recently had this fault, but not the result of a oil change. The car would not rev over 3k just as if the speed limiter had been activated. Went down the turbo route, blocked cat, fuel system tried absolutely everything new ecu.
no fault codes stored or current when the problem occurred.

Turned out to be the oil level sensor in the sump, it also incorporates a oil temp sensor that the ecu refers to. It was out of spec on the actual values in the diagnostics, it was off the scale reading 170 degrees!

It would appear that the ecu limits the engine output to avoid damage if the oil temp is to high. I did not know this, I knew that this could happen if the coolant temperature went to high. I saw this quite early on but dismissed it, but after having the turbo,cat,fuel system, intake manifold and just about anything else you could think of apart went back to this and replaced the oil level sensor out of desperation and that cured it.