M271 Engine change

[CraigHitchman]

Hello,
I change my M271 engine in my C200 2008 Mercedes(W204) because it had skip timing and damage the valves. I now have in a similar M271 but with different engine number the first six numbers on this engine is 271948 and my original engine number is 271950. Now the car will start but when put in drive gear or reverse there is no pedal response however when in park the car has pedal response and will rev. Can you tell me what's causing this issue??

 

[markjay]

Did you get the replacement 271.948 engine complete with the ECU? Or are you using the original ECU from your old 271.950 engine?

The reason for asking is that the fault seems to be software related.

Do you (or the garage) have STAR?

 

[CraigHitchman]

Did you get the 271.948 engine with the ECU? Or are you using your old 271.950 ECU?

The reason for asking is that the fault seems to be software related.

I am using the old ECU

 

[CraigHitchman]

Can my ECU be reprogram to work this engine???

 

[markjay]

...and, on another note, I am assuming/hoping that you have inspected or changed the camshaft sprocket wheels on the replacement engine?

 

[CraigHitchman]

...and, on another note, I am assuming/hoping that you have inspected or changed the camshaft sprocket wheels on the replacement engine?

No i don't think that was done by the mechanic???

 

[markjay]

Can my ECU be reprogram to work this engine???

I don't know if the ECUs are in fact different, and if they are different, then I don't know if they can be reprogrammed, someone else might know though.

But my feel is that if you have kept the old ECU and you are having the issues you describe, then the ECU will the be the first thing to check. Possibly just uploading a software update might fix it, or perhaps you'll need to SCN code the new engine to the car so that STAR downloads the correct software. Hope this helps.

Also, had you installed the ECU from the donor car, you would have needed to also get the EIS from the donor car (or replace/program it etc).

 

[markjay]

No i don't think that was done by the mechanic???

Well, surely you don't want the replacement engine to go bang as well.....? The timing gear failure is a known issue. The original MB camshaft sprocket wheels are made of chocolate... not aided by the fact that it's a single-chain design.

Ideally you'll install a new timing gear kit that will include two new camshaft sprocket wheels, chain, tensioner and guides. Or at the very least have the cams cover removed and the sprockets and chain inspected for wear and tightness.

 

[CraigHitchman]

I don't know if the ECUs are in fact different, and if they are different, then I don't know if they can be reprogrammed, someone else might know though.

But my feel is that if you have kept the old ECU and you are having the issues you describe, then the ECU will the be the first thing to check. Possibly just uploading a software update might fix it, or perhaps you'll need to SCN code the new engine to the car so that STAR downloads the correct software. Hope this helps.

Also, had you installed the ECU from the donor car, you would have needed to also get the EIS from the donor car (or replace/program it etc).

Yes Thanks for this will get someone to do a star diagnosis on the car tomorrow and update but do you know if this engine can work in the car??

 

[markjay]

Yes Thanks for this will get someone to do a star diagnosis on the car tomorrow and update but do you know if this engine can work in the car??

I don't know specifically for the M271, but my experience with swapping engines in general is that as long as the ECU (and EIS) are happy, there shouldn't be a problem.

 

[CraigHitchman]

I don't know specifically for the M271, but my experience with swapping engines in general is that as long as the ECU (and EIS) are happy, there shouldn't be a problem.

When i do a search on the new engine i realize it came from a w203 mercedes while my car is a w204. I am just hoping the Star update can fix the issue

 

[DITTRICH]

I am sorry to hear of your troubles but this is the right place to get free advice.
There is a whole thread on this engine on the forum.

 

[markjay]

As far as I can see the 271.948 came from a C230/CLK230, and will be more powerful than your old C200 engine. At the very least, both the compression ratio and the supercharger boost will be different. The old ECU will almost certainly not work with the new engine.

What I don't know is if you need a new ECU (and reprogram the EIS), or the old ECU can be reprogrammed and reused.

And, while I am sure that the ECU needs to be sorted in any event, I can't be sure if your current problem is indeed the result of the ECU mismatch, or perhaps it's the result of another unrelated issue.

But get the ECU sorted first, and take it from there.

 

[CraigHitchman]

As far as I can see the 271.948 came from a C230/CLK230, and will be more powerful than your old C200 engine. At the very least, both the compression ratio and the supercharger boost will be different. The old ECU will almost certainly not work with the new engine.

What I don't know is if you need a new ECU (and reprogram the EIS), or the old ECU can be reprogrammed and reused.

And, while I am sure that the ECU needs to be sorted in any event, I can't be sure if your current problem is indeed the result of the ECU mismatch, or perhaps it's the result of another unrelated issue.

But get the ECU sorted first, and take it from there.

That's the million dollar question i need a answer to, can my old ecu be reprogrammed to match the new engine??