ECU Remap

Hintza

Can you guys give me the pro and cons of an ECU remap. With emphasis on a 3.0 CRD Mercedes in the Jeep Commander/Grand Cherokee.

Car will be used for towing horse trailer mainly <2 tonnes mostly, but on the odd occasion might approach 3 tonnes with a flat bed.

Annual mileage will be about 8,000 - 10,000 miles sometimes sitting for 3-5 days at a time.

Power increase would be a bonus but I am looking for more MPG which I guess I'll get if the car is running a shade more efficiently.

Thoughts? Worth the expense?

JustinR1979

Mapping transforms turbo diesels. Will be like a different car.
As for saved mpg, I've never seen it. Only from seeing how much better it is on fuel, so you'll drive steadier to test it.
I had a 110tdi Passat done, went from painfully slow (after owning an M3) to a fun pokey car.
Brother had his 204bhp 330d bmw mapped, and it gave my M5 a hard time on the drive home. That'll spin through the first 3 gears now in the dry.

k3lvc

Well worth the expense if you're going to exploit the changes - I did it for the extra overtaking poke and to make my C320CDi Merc into something special i.e 50mph to 100mph (abroad of course) in the blink of an eye

Would I do it if I didn't want the extra performance - no

Did it save me money - no (but it did give the same indicated MPG despite the extra performance)

Did it put a mahoosive on my face when I buried the pedal - :D:D:D:D:D:D:D:D:D:D:D:D:D

For your purposes if you did it I'd make sure the horses had some extra padding or were belted in

Stoke

The thing with remaps is when they save it'll save you money by making your car more economical, it will, but it will in certain cases. I know someone who had a Golf TDI remapped. It made the car significantly faster, accelerated massively quicker. They also claimed he gained economy. However in reality, he lost economy around town and slower driving. He gained economy while hammering it down the motorway averaging something like 68MPG while doing 75MPH which is seriously impressive.

I think remaps are a great. The fuel consumption you lose will be quickly offset by the amount of added enjoyment

JustinR1979

I've never lost mpg, but I get it done by someone decent

Hintza

My understanding is that the increased mpg is from more efficient fuel burn, quicker into a higher gear and generally just being a little more efficient all round.

What worries me is I just drive harder and it is all for naught....lol.

Stoke

Hintza wrote: »

My understanding is that the increased mpg is from more efficient fuel burn, quicker into a higher gear and generally just being a little more efficient all round.

What worries me is I just drive harder and it is all for naught....lol.

As I pointed out above, you'll probably gain economy driving harder. I assume the extend your 5th making it more economical down the motorway etc.

Hintza

Auto box .

Any good resources to read up a bit more I have done the old google search but that only turned up the odd snippet.

JustinR1979

Car makers spend billions to make engines efficient, materials light etc for lower emissions and higher mpg.
I don't believe a chap with a laptop writing generic maps can achieve better mpg and better performance at the same time.
I've always equalled the mpg when on a run.

k3lvc

Assuming it's a Merc engine/gearbox unit then I'd be starting my reading here http://www.mbclub.co.uk/forums/index.php

atrixblue.-MFR-.

please check condition of turbo before you go remap, a worn turbo shaft and bearing (evidence by slight play in the impellar shaft when the hose is removed from the turbo) once you go remap and boost increase can kill it quickly.


please have the intercooler cleaned if you haven't had it done, turbo diesel intercoolers do pick up oil residue inside, restrict air flow and hampers cooling, make sure all seals and hoses and breathers are sealing and tight, etc cleaning out intercooler and checking for issues prior before remap will insure that a rolling road test on air flows etc are at their peak of performance to ensure you get a good map.


I have seen loads of diesels go for a map that have dirty interoolers, leaking breather pipes and inlets, and have come out improved, but as they did the map live and not just flashed the ecu with a pre built map lose out on many aspects they could have done with a properly sealed healthy engine.


OH PS I would have live map rather than a ecu reflash with a pre built map.