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Discussion Starter #1
Ive never felt the re-map I had has been that satisfactory and i'm thinking of having my 320D E46 de-mapped but before I do this i'd like some feedback.

Three things have made me think a de-map may be the best way to go.

1)After having the remap the engine sounds different. Maybe this is just diesel knock, however, it doesnt purr as it used to.

2)Yes, there is improved acceleration etc.,but it not as good as it was when I used a tuning box. The acceleration is patchy or bitty with a big whoosh when the turbo kicks in. With the tuning box it was very smooth through the gears, the improvement in acceleration was down the line, and better.

3)The final reason I am considering a demap is that my fuel consumption has gone up substantially. I was averaging about 43.8 mpg but its now gone down to about 39.8 mpg (despite driving economically). This is a reduction in fuel economy of about 10%

I spoke with the people who did the re-map. Theyve got a good reputation. They double-checked the remap to see if it had loaded amiss which it hadnt. Im thinking about going back to the tuning box.
 

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your engine will prolly thank you for it (a demap) in the future. less destructive torque n stress on the drivetrain and engine components..
 

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Its up to you-If you're unhappy with the remap then it's definately the right thing to do to go back to its normal map..:thumbsup
 

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Discussion Starter #5
The people who did the re-map have a good reputation amongst BMW owners who've remapped with them. I dont know why they are all saying its great.

Iam especially disappointed with the increase in fuel consumption. Its reduced fuel economy by about 10%. Thats equivalent to an increase in fuel cost of over 10p per litre. That's a heck of an increase. Anyone else seen there fuel economy diminish so much after a re-map. Would like some more feedback on this.
 

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increasing the HP and torque and spinning a turbo harder etc etc is hardly ever gonna improve MPG on most ppls drving styles especially on an urban jungle animal..simple engineering logic..
 

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Sounds to me that the map you had wasnt of all that good quality... It should be just as smooth if not smoother on delivery - or so i've heard anyway. I think you should maybe have a work with Motech Mike, he's a genuine bloke he'll tell you what he thinks of it all...

Good luck mate.
 

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not always, a lot of cars are set up to run rich as standard at low revs. leaning the maps out low down and adding more fuel up top can improve MPG.

ive yet to see a diesel owner with a remap that dosent hoon it everywhere when the oppertunity arises and has a remap for MPG reasons it all depends on how a car is driven if any mapping is going to be of any MPG benefit....:shifty:

by definition a turbo diesel developes its power early in the rev range, hence the high torque characteristics (it has to overcome the resistance and inertia in a limited rev range) of the engine and hence its so easy to map in the first place..

i sound like a nerd the price of 27 years working on the things.:jaw-dropping
 

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Sounds to me that something is bad with the remap, mine is 330 petrol and after remapping the engine is much smoother through lower rev range and i average 31 mpg, not bad for a 6 pot, thought i didnt have an aggresive mapping, just one to smooth out the flat spots.
 

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Sounds to me that something is bad with the remap, mine is 330 petrol and after remapping the engine is much smoother through lower rev range and i average 31 mpg, not bad for a 6 pot, thought i didnt have an aggresive mapping, just one to smooth out the flat spots.

a remap is only as good as the condition and health of the engine itself and any decent future maintenance..

a decent mapper will do an engine health check and advise on a map or not on the health status and mileage of the engine..

a strictly in it for the money mapper won't..and theres plenty of the latter type about..
 

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Discussion Starter #12
increasing the HP and torque and spinning a turbo harder etc etc is hardly ever gonna improve MPG on most ppls drving styles especially on an urban jungle animal..simple engineering logic..
I used a Tuning Box and not only was it much smoother but the MPG improved. Not so with the re-map.

The people who did the re-map had an underlying look at my engine and there were no issues. As I said before, withour naming names, the people who did the re-map have a good reputation amongst BMW owners. I was told that the maps they installed had been loaded on many other diesel BMW's and that there were no complaints.

Maybe some people are easily pleased. As it is at the moment i'm considering abandoning the re-map and going back to the tuning box
 

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Sounds to me that something is bad with the remap, mine is 330 petrol and after remapping the engine is much smoother through lower rev range and i average 31 mpg, not bad for a 6 pot, thought i didnt have an aggresive mapping, just one to smooth out the flat spots.

you can't get aggressive power n torque mapping on petrols theres no secret or hidden bounty of untapped power to be had at all like diesels..
 

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Dactel - I have the same car as yourself and have been conssidering a remap for quite a while. I take it your model is 150bhp standard? As I have read that most remaps bump this up to around the 180 mark. Has your car been on a rollers to check this out?

Some remaps advertise an increase in MPG but surely if you tune your engine up to run faster then a decrease in MPG is going to happen.

I like yourself like the fact that the car doesnt drink fuel, so I can totally understand where your coming from.

....best of luck with whichever you decide to do. :thumbsup
 

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Discussion Starter #15
Hi Seb. Yes, I have the E46 M47N 150bhp .The theory is that after a re-map the car drives much more smoothly (through the gears) and this is where you improve mpg. Well thats the theory.

My re-map was done by reputable people. Im not sure what a 'rolling' test is, however after the re-map was done we took the car on the road and monitored performance via computer.

My mpg prior to re-map was 43.8, now its around 40.0. With a Tuning Box (speedbuster) it was around the 44.5, however I believe that they can mess with the reading. As ive said before though the Tuning Box felt better than the remap
 

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Hi Seb. Yes, I have the E46 M47N 150bhp .The theory is that after a re-map the car drives much more smoothly (through the gears) and this is where you improve mpg. Well thats the theory.

My re-map was done by reputable people. Im not sure what a 'rolling' test is, however after the re-map was done we took the car on the road and monitored performance via computer.

My mpg prior to re-map was 43.8, now its around 40.0. With a Tuning Box (speedbuster) it was around the 44.5, however I believe that they can mess with the reading. As ive said before though the Tuning Box felt better than the remap
Thanks for the info, makes it a lil clearer for me.....:)

If I was in your shoes with your situation then If I could it de-mapped for free then I guess I would, but best of luck with whatever you decide :thumbsup
 

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Hi mate, my E60 530d remapped by motech mike, goes like stink, drives like a dream and I never look back (well only to wave at the ponce who dares challenge me, lol)

I think i got a slight increase on my mpg but with a mix of heavy foot and long m way driving I am not sure.

All I know is I am very happy with my remap and current mpg :) Red

PS would recommend everyone get a remap and stop thinking about it (if you can afford it), my only regret is not doing it earlier!!
 
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