850 Motronic 4.3 to 4.4

[Gonzobard]

What are the benefits on an 850 of upgrading from Motronic 4.3 to 4.4? I see it mentioned but don’t know what benefits it brings. Thanks.

[Mkengineering]

Originally Posted by Gonzobard

What are the benefits on an 850 of upgrading from Motronic 4.3 to 4.4? I see it mentioned but don’t know what benefits it brings. Thanks.

Good question I also would love too understand this.

[winsox]

Originally Posted by Mkengineering

Good question I also would love too understand this.

From what i understand the 4.4 unit is :-

OBDII so you can use a normal code reader with it

Larger memory so you can have a larger map file (More adjustment data)

Slightly quicker Processor (Might be wrong on this)

Im sure that someone will add to this and correct where necessary

Data on ME4.3

http://www.paerl.it/volvo/Volvo%20Motronic%204.3.pdf

Data on ME 4.4

https://www.volvoclub.org.uk/tech/fu...B5254T-850.pdf

https://www.volvoclub.org.uk/tech/fu...254Tengine.pdf

[Cookeh]

As above, plus more tuneability and better mpg.

[Gonzobard]

Thanks Winsox, plenty of bedtime reading there. How is a swap to 4.4 made? Does it require a physical mod to the ecu or a total swap of ecu? Do people normally upgrade to 4.4 when having a re-map of their ecu? Thanks.

[winsox]

Originally Posted by Gonzobard

Thanks Winsox, plenty of bedtime reading there. How is a swap to 4.4 made? Does it require a physical mod to the ecu or a total swap of ecu? Do people normally upgrade to 4.4 when having a re-map of their ecu? Thanks.

You have to change the full ECU, it just plugs in.

The ME 4.4 needs some changes as it can cause the Electronic Climate Control to fail.

I think if your doing basic mods you can just use the ME4.3 but if you need better maps and control you can go to theME4.4 System.

Shemtek is sorting mine out as im in the middle of an engine build and hes the man that will be installing the 4.4 system, turbo and tuning for it.