I installed MTH last week.

I also reset the ECU through the dash button.

Just prior to this I was getting 22's city, now I can't get above 16, driving the same. Is this a function of the MTH or does this usually happen after a reset?

 

My recent update yielded great gas mileage for the two tanks, but the third tank had poor mileage again. 25mpg, 26mpg, now I'm back down to 22mpg

 

as settings in the computer can change how the trip comptuer calculates it.

In general, there are two competing forces on MPG...

Leaning the mixture increasing mpg for a given RPM during hard acceleration....

More torque, that invites you to play more with the gas, decreasing MPG...

Your results may vary. I've found that for all the mod's I've added, and all the changes in driving style, I still get within a few MPG of when the motor was stock and broken in....

Matt

 

I am waiting for my MTH... and have been wondering if anyone noticed (after uploading the MTH) any change in gas mileage?

I have an 05 MCS JCW... and when I recently had the resonator removed from the JCW exhust, I not only had a dramatic increase in power... but the gas mileage also improved greatly! I now have a 5 to 6 miles per gal increase/improvement during freeway driving. I am hoping the MTH tuning doesn't mess with this success.

So I'm also interesting in hearing others gas mileage reports... after running the MTH mapping... has your gas mileage changed at all?

 

Hi,

I've been using MTH for quite sometime already. I do notice after installing the MTH, I get less mileage... I asked few of my friends who have stock ECU,they tend to get more mileage than I do. I do think that with MTH, you'll get more POWER and less mileage...

 

How much less? How are you calculating?

 

Do you have any idea (on an average) just how much less fuel mileage do you get? What Cooper do you have?? Is it a stock "S"?? or JCW??


I just got my file back from Franz this morning... so I guess I am about to find out. I just uploaded it... and hitting the road soon to test it out.

 

If you read this before doing so - please do this quick test - flash the MTH, reset your avg reading only - drive around to see if you if it changes or not. If it does, we know it's a function of MTH. If it doesn't, reset your computer through the dash, then drive around and note again.

 

Well, this way is not the best way to calculate the mileage. I just calculate how far I can go with full petrol in the tank till i reach the 1st bar with the warning lights on. I did it several times. I switched back to the original file and i get more mileage...like 30-50km.

I'm having a 15% pulley with Alta CAI. At the end of the day i ended up using back the MTH, I cant live without the power.

 

Does anybody know the convertion? km to miles? (oh I guess I could go look at the speedo).

 

I will do this... but I usually like to gauge mileage on a longer freeway road trip. One that keeps me at a constant speed (no stop and go). I use that to gauge any changes, because I feel like it gives me less variables. Otherwise, it's just one big variable average... and thus provides non-acurate data.

 

30 Km is about 18miles
50km is about 31miles

 

YIKES! But then again that's per tank of gas... and not a particularly acurate way of gauging the amount of fuel used. Well, in the weeks ahead I will find out how it effects mine. But in the end - unless it's REALLY bad - I will take the power over fuel effiency any day.

 

Yes, like i said.. its not the best way to observe the amount of fuel used. I have no on board computer on my car... Only the temperature and the speedo.

 

Well, I am using my on-board, and have very consistant results for my drives to work. It's clearly dropped 8MPG so far. I will test this monday by reflashing to stock, and not resetting the computer, see what it gives me.

 

YIKES! Here's an interesting question: What controls the on board computer? Does flashing the ECU have any effect on how the on board computer... computes gas mileage? Other than the results from engine performance changes... you know what I mean.

 

Franz did mention that mth changes the torque caculation. I don't know if that would do it. To be clear, my mileage didn't go down. It went up and back to normal, maybe it would stay up if I weren't reving it up all the time now.

 

Here's my initial reaction to driving the car. Initially, for the short trip on the freeway, my gas mileage appears to be the same. Time will tell.

The car deffinately runs smoother. I can tell that the power available throughout the gear range is more consistant. The car even seems to idel smoother (not that I thought it was rough before). However, I swear my "borble" is quiter and slightly less pronounced. Something I'm not sure I like.

Back on subject... time will tell on the gas mileage. Your actual results will certainly vary.

Again, my setup is an 05 MCS JCW, with the resonator removed.

 

Yes, my "borble" has mellowed out a little too. It still does it when I rev it up, just less between shifts and when coasting. This is different from other mth flashes and may be a side effect of the smoother cruising throttle response. This is still my favorite mth flash yet.

 

Mine is exactly the same.

 

OK, after driving another 50 miles tonight it's back to normal. I reset just the avg. setting and did some mixed driving - back to mid 20's. Maybe it just took a while or several cycles.

 

I think I should get the on board computer installed... my life is harder without it.

Basically I manage to run for abt 400Km per tank... do you guys get the same figure?

 

I found that my fuel mileage actually went up.. based on driving style.


example.. took the car to track day at a particular facility.. drove the hell out of the car.. got 12.6mpg..


did a track day, same track, same general weather conditions, had just put in the MTH map.. drove the hell out of the car.. better (faster) times.. got 14.2 mpg..


in general daily driving , i notice a 2-3 mpg improvement.

if I wanted good gas mileage.. I would not press so hard on the right pedal..

 

Yeah, press the middle pedal more!!