# Results of ECU remap & Tune it module



## RichardD (Sep 14, 2009)

This is our first MH and since owning I have been religiously monitoring my fuel consumption using the 'brim to brim method' and recording on an excel spreadsheet.

I then decided to fit a Tune It module to try and improve fuel consumption which was disappointing and then had an ECU remap carried out by our local tuning expert which also produced no improvement.

The results are as follows: -

The first 2800 miles produced an average of 24.17 mpg on the standard Fiat configuration. There were 2 trips, one around northern France, St. Omer, St Valery, Honfleur, Dieppe etc. just getting used to MHing. The 2nd trip was down to Mont St Michel and into eastern Brittany, Erguy, Binic etc. Best figure was 25.8mpg but this was on the autoroute back to Crotoy with a tail wind. Weight was probably around 4300kgs.

Then I had the Tune It module fitted following a chat with the guy at the Shepton show plus their special offer price. 

We then did just over 2500 miles on a trip down to Agde and the Carmargue area and back and this produced a figure of 23.24 mpg which was disappointing on such a long trip using mostly free autoroutes down through the centre of France. Best figure was 23.81mpg down the A75 from Clermont to Agde, which I was surprised at considering the climbs up over the Cevennes.

Removed module as I had a sale or return agreement based on increased mpg which it failed. However, the module made the engine sound smoother and it had more power.

We then did a further 2400 miles on a trip up through Belgium via Brugge and Antwerp across to the Genk area and then back down through the Ardennes to Paris. From there down to the Loire and following it right out to the Atlantic at St. Nazaire and then following the coast up around to Carnac before turning for home. This produced a figure of 22.43mpg again a further drop in mpg even though the engine was back in standard Fiat specification. Could be down to possibly driving a bit faster as I've now got used to the size of our outfit. Best figure was 23.66 mpg from Antwerp through Genk and down to Chateau Thiery. 

Then had the ECU re-mapped and have covered almost 2900 miles on 4 trips. Abbey Wood twice and one to Chester Fairoaks, Bury Country Park, Chatsworth. The other trip was down to the Loire near Blois. This has produced a figure of 23.02 mpg with a best of 24.31mpg on the recent trip to Abbey Wood and back. The Loire trip produced a figure of 23.78 mpg.

Again no improvement in fuel consumption but the engine pulls better.

So in summary the figures were: -

2700 miles in standard Fiat spec produced 24.17 mpg
2500 miles with a Tune It module produced 23.24 mpg
2400 miles again in std Fiat spec produced 22.43 mpg
2900 miles with an ECU remap produced 23.02 mpg

My MH has the 160bhp engine and the Comfortmatic gearbox. Weight of van varies from around 4000kgs up to 4400kgs depending on journey. I try and drive at around 55 mph on single carriageways and around 65mph on dual/autoroutes. This produces the best consumption figures as I tried dropping the speed to around 50mph but the gearbox won't get into 6th at this speed so the consumption suffers.

So make of this what you will, but it's is clear that the claims of these engine tuners to increase mpg is exaggerated in my view.

If you want more power chose one of the many suppliers out there but mpg, take with a large pinch of salt.

All in all and knowing what I know now, getting 23 to 24 mpg from a 4300kgs MH is not bad.

Richard


----------



## VanFlair (Nov 21, 2009)

Interesting a scientific analysis, but at the end of the day engines only produce power if you give them fuel to burn, if you can get more power and smoother running for no worse fuel consumption you are doing OK, we have ECU remap and would conclude same as you icluding getting used to driving a big lump so going a bit quicker.

Martin


----------



## 747 (Oct 2, 2009)

I am a bit surprised at the lack of difference with your experience. I did as well (and better with decent Motorway and Dual Carriageway runs) on a heavier van with an overcab (therefore not so streamlined).

I found my Tunit box gave a marginal increase in mpg but nothing to get excited about. Your van has (I assume) a 6 speed box which should cruise better than my 2.8 jtd, 5 speed box did (although I had the 'long' 5th gear).

Perhaps you used the extra power with a higher average speed which could result in there being no change? I found that cruising at around 2,000 rpm (56 to 58 mph) was the optimum for fuel efficiency. Now I will have to learn all over again with my new van with a 6 speed box. I have always believed that a diesel engine should be run at no more than 3,000 revs when changing up and 2,000 when cruising.


----------

