W203 OM606 conversion, anyone done one

[Dánáidh]

I have a old 52 plate w203 auto sitting about with a engine that's slowly dying...... Won't accelerate over 60mph and for have 143bhp and being out ran by a pug 107 it's needing a new life before the wife convinces me to break it.

I've always loved the om606 engine so the cogs started turning and now I want to try and fit, run and tune a om606 in my w203. I have a rough idea how to make it fit but I have no idea about the wiring, gearbox and rear diff.

Anyone done one or can give me some pointers?

Thanks in advance

Daniel McGinley

[ChasR]

Wiring I suspect would be the hardest problem.

Have you made any attempt to fix yours? It would be easier to fix than throwing in an OM606 and magically expecting everything to work.

[Dánáidh]

I've tried evereything, even swapped some bits from my working c200 sport and it made no difference.

Ive done a decat, cleaned egr, intercoller, throttle body, air filter, oil filter, injectoprs, feul filter, throttle pedal, maf, done a gearbox sevice. am at the stage where i don't know what else it could be, I could easily break it for the bits i need for my other daily w203, but i want to try an save it before i do condemn it (even through with 180k and rough bodywork it prob worth just killing off)

[ChasR]

Have you tried Star or a decent Merc diagnostic system on it like CarSoft?

[carat 3.6]

It would be far simpler and cheaper to just fix what you have, as said above a decent diagnostic system will find the problem easily.

But to answer your question, the om606 will physically bolt in to a w203 using of the shelf parts, swap the injection pump to a older mechanical version to make it run. The electrics in the w203 wont like it though, and will need some mods.

[squonk]

Without the original ECU I doubt that at would even recognise the ignition key. Also the majority of the electronics are most likely can bus so will create a nightmare in even getting the simplest of things working such as instruments.

This swap could end up being both complex and expensive!!!

[loudsam]

You can do it mate the om606 will bolt to the w203 gearbox and depending on if it is a Manila or auto you will need a gearbox controller for the auto box you will have to do some modify with star diagnostics for some sensor but should be easy enough to sort.

I’ve been contemplating putting a 606 in to an S class which I thing would be fun

[grahamk]

You can put an OM606 in a w203 but there are a lot of things to consider.

If it is a petrol you will need to get a diesel diff and suitable gearbox (the petrol 722.6 autobox is not strong enough) you would need to get one from a c270 cdi if you plan on hiking the power up as even the standard 722.6 in the e300td is not man enough for a tuned 606.
IF you get a 722.6 transmission from a c270cdi you would need to rob this transmission controller or get a stand alone ofgear one

Regarding the ECU, you can run an ecu from an OM606 donor w210 to control the standard EDC injection pump BUT you would have to get one from sean treacy, this way it will have all the daft key and immobilizer/limp mode curse word removed.

All in this would not be a cheap project.

The 606 is a fantastic engine but you'd be cheaper fixing your's or selling it and getting a c320cdi or c270cdi and tuning the nuts out of that.