Failed remap issues

[hedges88]

I went to a professional tuning company (along the lines of Celtic etc) to have a remap on my Mercedes W169. I do not want to debate about naturally aspirated remaps it's a can of worms that never ceases. However I thought I'd at least try getting a remap and seeing if I could get any noticeable power difference, powerband changes and economy. I am satisfied with the cars performance normally but when loaded with people and cargo it feels a bit underpowered

I was advised that my ECU was "VR" which I've had to look into since but my understanding is that it's current map could not be extracted or "backed up" before writing a new map. The company did everything right, stabilising the power from the battery etc. The remapping company has obviously used a file available to them from their source of maps, the same files every other re-map company must use as they all show the same power increase. AFIK there were no issues during the writing of the new map.

The remap was not a success, though there was no engine light etc, the red battery symbol appeared, meaning alternator fault, despite the service menu showing the alternator working just fine. ESP/ABS/TPMS/Hill hold all unavailable. The engine was limiting itself to just about 2100 rpm with a very hard cut limiter. The only fault code was that the entire canbus was implausible. The tuning company bent over backwards to provide customer service, paid for a taxi home and everything which is why I won't name them because they have been great.

They had an MB specialist come and write an original Mercedes map and all is well again. Company are refunding the map and compensating taxi etc but don't feel comfortable attempting another or different map which is fair enough.

Cars running sweet as a nut, no fault codes or anything but I've noticed my short and long-term fuel trim is all over the place. I used to get an average LTFT of positive 1.9% and my short and long figures never went over +/- 10%, anything over 10% pos/neg is something I've always been told is a problem. I'm getting short and long term trims going as high or low as 29%

You can be on a motorway or whatever with constant throttle and it settles down, but urban driving and high load at lower engine speeds it starts behaving erratically. The service menu show's I think the same dates of software/hardware revision as before but the other text is definitely different., I can't remember what it said before but I know it's different now.

Are these extreme swings in fuel trimming to be expected as the ECU is having to re-learn and adapt etc? or is it possible that the firmware restored is incorrect?

All my keys worked, etc and all of the cars optional extras work as intended, so I don't think anything was recoded and the original ECU is still in place, just the engine firmware being restored. I just want to try and see if anyone knows if this isn't potentiality normal because if not I need them to check it again with them before declaring my problems to be completely solved.

Any advice appreciated!

[stevieturbo]

From what I gather, none of the companies back up or save the actual file/map from your car. And when they fk up and "return your car to standard".....it is just yet another generic file that might apply to a car like yours, but almost never the actual information that came from your ecu.

What have Mercedes said about it ? Are they happy there are no faults stored anywhere ?


Large percentage swings would be odd, but perhaps give it a few days and miles ? or how much has it been driven since the fiasco ?

But yes...people wanting remaps on n/a cars....and expecting any real gains is a bit LOL.

[hedges88]

stevieturbo said:

From what I gather, none of the companies back up or save the actual file/map from your car. And when they fk up and "return your car to standard".....it is just yet another generic file that might apply to a car like yours, but almost never the actual information that came from your ecu.

What have Mercedes said about it ? Are they happy there are no faults stored anywhere ?


Large percentage swings would be odd, but perhaps give it a few days and miles ? or how much has it been driven since the fiasco ?

But yes...people wanting remaps on n/a cars....and expecting any real gains is a bit LOL.

That's exactly I think what they were telling me, ECUs like mine cannot be read. Hence the element of risk. You can see on YouTube how they extract data from these ECUs by literally opening them up etc

So Mercedes-Benz themselves haven't seen the car, but they said a Mercedes specialist had worked on it. Mercedes specialist could for all I know mean a man with access to developer mode or online coding with XENTRY had a bash at saving it. I have XENTRY myself and the ability to code but as I have a Tactrix Openport and not an official SD multiplexer I would never risk coding myself.

So the company corrected me when I said "so it's just a generic map" because they say that these files have been generated by a healthy donor car on a dyno, with optimising and tweaking the map for the advertised result but then of course it is shared and applied to other cars. Nothing beats a custom individual map because every motor is different but it's very pointless for a little naturally aspirated lump like that.

I've seen very good remap results on large naturally aspirated engines. It just depends on so many things, if the original map is safe, sensible and suitable for many markets or if it's already aggressive and pushing the envelope. I don't usually believe the quoted figures for these remaps, in my case an extra 10bhp, but I know for a fact that sometimes someone can make a better map than the OEM that is smoother and has better throttle response. As I say it's a can of worms I don't want to open but if I want to spend money on trying it, it's personal choice.

I just don't understand why her values are all over the place, though I did read an article on fuel trims today that was comforting as it said that the values could potentially take hundreds of miles to stabilise. As I say, all is well with no fault codes and driving wise no different from normal, fine with just me but frustrating with passengers and cargo. That's one of the reasons I was willing to risk it for a biscuit, it literally just needs a little extra torque to make it perfectly adequate.

I took this video, this is after a period of normal driving of what the fuel trims look like at idle and when giving some revs. Never seen values so extreme before the attempted remap. Nothing physical has changed, no obvious vaccum leaks etc. I've just never seen values above 10%, you will even notice I have torque flash if a trim reaches double digits because I've always been told you don't want to be seeing double digits for fuel trim.

Hoping this is just part of a long adaptation process because I don't want to tell the remap company all is well if something is seriously screwy.


https://vimeo.com/685045638

[stevieturbo]

If the tuning is correct and all aspects of the car are healthy, trims should always be small.

Excessive trims either way, indicate something is not happy.

You're in an awkward sport now. I guess you can assume that the car was all healthy before this escapade ? and trims were all normal etc.

So the programming that is now in the ecu, is less happy or correct for your vehicle. I guess one possible "fix" attempt, is seek out a reputable ecu remapper who will actually tune the thing, instead of loading in random crap they know nothing about.

[hedges88]

stevieturbo said:

If the tuning is correct and all aspects of the car are healthy, trims should always be small.

Excessive trims either way, indicate something is not happy.

You're in an awkward sport now. I guess you can assume that the car was all healthy before this escapade ? and trims were all normal etc.

So the programming that is now in the ecu, is less happy or correct for your vehicle. I guess one possible "fix" attempt, is seek out a reputable ecu remapper who will actually tune the thing, instead of loading in random crap they know nothing about.

Exactly, yes her trims were always in single digits, she had a tendency to run ever so slightly lean and would run a long term fuel trim of around 1.9% positive. On a very long journey it might come down to 1.2%. I know zero is ideal but for 95k and all that wear and tear I found her usual figures to be more than acceptable. Short terms would usually be in the 3% range and you would only see occasional corrections.

The dates for the ECU match my car, though mine was manufactured in 2008 and registered in 2009 it's one of the first facelift W169s. My theory to the technician that flashed the tuned map was that he had flashed the map for the A160 Blue Efficiency. Same engine (M266.920), longer gearbox and a variable load alternator with an additional auxiliary battery in the cargo area to remove strain from the engine. This is why I believed it had the alternator warning and limp mode and completely implausible canbus signals. I've noticed that websites like Celtic tuning even incorrectly label the A150 as blue efficiency.

They say there are two maps available for the car, and that there is one single letter of code between them. I could go to any tuning company and they are going to be looking at the same maps. They say the people who deal with the files are Italian so I'm assuming we're talking about FG Galleto.

If the remap company pay for the file and there is an issue then do the tuning company not have to investigate? The remap company has said they will not be offering remaps on my vehicle again which is good

Other possibilities I'm considering is during it's time not having any clue about itself or what it's engine was doing it's got petrol into oxygen or catalyst sensors.

I will wait for the tuning company to get back to me but I don't think I can accept that the car is okay, even if it's got no faults and is fine to drive because come my next MOT I could get a nasty suprise on the emissions test?

[Ouroboros]

it amazes me people are so quick to mess with very complicated systems, using cheapest methods available,

The majority of remaps are off the shelf all fit all.

Any remap should have full diagnostics done, then a file dump, then rolling road, then a remap if O.K., if not then don't, but can't imagine people would pay.

There are loads of parameters, leaking injectors, wouldn't show error message, other faults. the issue is you are then remapping a faulty car.

I would look at getting replacement ecu.

[liner33]

A lot of this issue is probably due to the fact they cant extract the stock software, to ensure the remap was compatible . To be honest a remap on a n/a engine rarely yields significant improvement , most of the time the improvement is due to changes in the throttle mapping , something a pedal box or sprintbooster can achieve risk free

As asked how many miles have you covered on this new software , could it be the fuel trims have not yet stabilised ?

[eliot]

presumably all they can do on an na engine is give it more timing and allow it to rev higher - which are really just eating into the safety margins - as long as you are aware and comfortable with that then fine - otherwise just get a more powerful car.

[stevieturbo]

hedges88 said:

If the remap company pay for the file

IF.....

Some just obtain a load of generic crap and chuck them in peoples cars. And most have zero actual tuning knowledge.

And all of the above, is why I doubt I would ever let any such place "remap" any car I own.

You are now in a situation where you may need either a correct map for your car, or a correct tuned map from an actual reputable tuner.

Your existing map is gone, never to be found again unless Mercedes are able to flash something in. Although I'd guess that would cost a fair sum.

[stevieturbo]

eliot said:

presumably all they can do on an na engine is give it more timing and allow it to rev higher - which are really just eating into the safety margins - as long as you are aware and comfortable with that then fine - otherwise just get a more powerful car.

there are a lot of things they can do, but it's not like decades ago where engines and systems were more primitive. OEM are providing excellent performance these days, albeit under emissions restrictions. It's just harder for Ace Tuner...aka Joe Bloggs to achieve good gains.
But they do need to be good to get those gains, and not negatively affect anything.

Buying generic files from some random place on the internet then selling them to people whilst very profitable, is pretty st move when they really know little about it.

Maybe try the likes of Motorsport Developments ? Or Rica tuning get good reviews.

Pretty sure MSD do actually do all of their own tuning though and have been in the game for a very long time so can do the whole dyno thing etc etc on your specific car, tuning to ensure all is good.

[hedges88]

eliot said:

presumably all they can do on an na engine is give it more timing and allow it to rev higher - which are really just eating into the safety margins - as long as you are aware and comfortable with that then fine - otherwise just get a more powerful car.

I don't think any of these off the shelf maps would allow for higher revving, your not going to get any more power that way. But yes it's mostly timing and A/F ratios. There's a lot of variables involved. One thing would be the manufacturers map not being optimised for fuel available. I doubt a lot of standard N/A cars, even modern ones, will take advantage of Shell 99 etc. Performance N/A cars especially direct injection ones need high octane fuel to work properly, but run of the mill stuff isn't programmed with that in mind. Some manufacturer's maps are very conservative and restrained and can be improved upon and some cannot. You would get much more gain's remapping an E46 330i than an M3 for example, there's not much room for improvement on the M3.

The engine in question is odd, I had to make a post a while back asking why a naturally aspirated engine would quote a torque figure as a range rather than a peak as I'd come to expect. Mercedes claims it can give 103 lb/ft from 3500-4000RPM, but it turns out it's clever use of a good variable length intake that the engine was designed with in mind, apparently VLIMS are tricky to do maths for. In my case as well peak power (95PS) is given at 5200RPM. However the torque graph shows it then goes on happily making that power all the way to 6000rpm. The limiter doesn't even kick in until 200rpm after that where it's still pulling cleanly! It is a SOHC 8v design nice and simple, although in 2004 when introduced I guess you could say 11:1 compression was pretty edgy for a small N/A petrol but not today where we have petrols with compression ratios over 14 that are even acting as part time compression ignition engines and part time spark ignition, I think it's Toyota that's got those or one of the Japanese companies anyway I'm seriously digressing.

Yes you do accept risk if for example you have an old TDI or turbo petrol remapped that you are going to risk exposing existing weaknesses, stress on the clutch/gearbox or driveline etc. A N/A remap shouldn't be causing much in the way of stress because there simply isn't going to be much extra gain. In fact a lot of companies now are offering efficiency remaps alongside performance remaps for turbo diesel and petrol cars. That's how I look at an N/A remap, more like an efficiency remap. Not anything in the way of power very much but perhaps more in responsiveness, fuel efficiency and emissions. Just optimised is how I would put it, I wanted to make sure that my car was optimized, things have changed in 13 years and if someone genuinely has proof that they have achieved gains with a similar car then that would have my interest and my money.

This sort of erratic fuel trimming though is NOT what anyone should expect or accept from a remap. It's only been 50 miles or so, she may well settle down. The company has been great in their support and it's been an awkward situation for all involved. As for people who say get a faster model etc, sometimes you just got to play with the toys you've got

W169s are a minefield car, every single one up for sale is up for sale for a reason. I'd love a nice A200CDI, would suit my needs perfectly but these cars make Citroen's look conventional. Clutch changes or CVT issues are just making them disappear by the day. Having one that's in good working order, clean and rust free with no apparent mechanical issues is not one you part with easily. I can have a motability car if I want, but my A150 does not cost me £76 a week to run and there is nothing like them anymore and never will be. It's 2mm shorter than the latest Ford KA but has as much room inside as a Golf or Astra. They are incredibly safe and have features that are unavailable or optional on brand new cars. My partner's incredibly expensive F21 diesel doesn't even have front parking sensors, and the legroom in the back truly is for children.

In days past people would take their carburetted car in for a tune up if they were keen on keeping it running as good as can be. I guess I've done the modern day equivalent really.....

[hedges88]

stevieturbo said:

IF.....

Some just obtain a load of generic crap and chuck them in peoples cars. And most have zero actual tuning knowledge.

And all of the above, is why I doubt I would ever let any such place "remap" any car I own.

You are now in a situation where you may need either a correct map for your car, or a correct tuned map from an actual reputable tuner.

Your existing map is gone, never to be found again unless Mercedes are able to flash something in. Although I'd guess that would cost a fair sum.

Hmmmm, you may well have provided a possible answer to my prayers if the trim figures don't settle down. Not that I would do it myself, AND you need online access but XENTRY does retain actual factory coding for the specific VIN being worked on, or at least I've seen the option when I had to reset my parking sensors but obviously I'm in offline mode. It is possible that all the original stock values for the engine control are in the ether of Daimler Chrysler's systems somewhere.

[stevieturbo]

You will never "optimise" anything...with a generic blind remap.

And your fuel trims now are not after a remap as such....as allegedly it has been put back to standard. Although standard for what....is harder to say.

Your best bet now might be to see if you can get another ecu from the same car that has not been tampered with, and see if you can have it programmed to your car/immobiliser or whatever it needs.

Then for a faster car....buy a faster car.

[carte blanche]

hedges88 said:

W169s are a minefield car, every single one up for sale is up for sale for a reason. I'd love a nice A200CDI, would suit my needs perfectly but these cars make Citroen's look conventional. Clutch changes or CVT issues are just making them disappear by the day. Having one that's in good working order, clean and rust free with no apparent mechanical issues is not one you part with easily. I can have a motability car if I want, but my A150 does not cost me £76 a week to run and there is nothing like them anymore and never will be. It's 2mm shorter than the latest Ford KA but has as much room inside as a Golf or Astra. They are incredibly safe and have features that are unavailable or optional on brand new cars. My partner's incredibly expensive F21 diesel doesn't even have front parking sensors, and the legroom in the back truly is for children.

Slightly OT but have you considered a Honda Jazz? We used to have a W169 and I agree they are great cars but have since moved to a Jazz as it's the only other vehicle I'm aware of that offers similar space in a small footprint. The MK3 facelift from 2018 could be had with a 130hp 1.5 litre engine which should be usefully quicker than your current car, or if budget allows you could go for the latest hybrid model which should also offer decent performance.

[hedges88]

carte blanche said:

Slightly OT but have you considered a Honda Jazz? We used to have a W169 and I agree they are great cars but have since moved to a Jazz as it's the only other vehicle I'm aware of that offers similar space in a small footprint. The MK3 facelift from 2018 could be had with a 130hp 1.5 litre engine which should be usefully quicker than your current car, or if budget allows you could go for the latest hybrid model which should also offer decent performance.

I was looking at the Jazz (1st gen) second hand before I had my mobility PIP, and next to it was a W169 A-class and I tried it and that's where the love affair began. The first one was a nightmare, had rust issues that were well hidden, had the poly belt whine that costs a fortune to fix. A/C didn't work and that stops the blue efficiency stop/start from working so I ended up returning it.

When looking at motability recently the Jazz was a huge down payment and the Honda E had no down payment. I couldn't get a free home charger because of some issues of property ownership around my parking space and upon seeing the state of the local charging network gave it up as a bad idea.

So unless something goes seriously wrong or the clutch goes im keeping my allowance for running the car I've got. It's still an incredibly clever and impressive piece of machinery that's hard not to fall in love with. I've always described it as the world's most luxurious Go-Kart and I think it's a good way to describe it

Look at some of the genius that went into the design;

[liner33]

I think there is a lot of confusion in vehicle mapping/remapping.

A custom map is expensive, itro £600+ why? because it takes a decent amount of time and usually a licence fee depending on ecu/model

Most remaps are generic, originally the map was custom written on a car on a dyno but then is repeated on many cars, provided your car is in good condition there is next to no risk and they work well.

A lot if not most companies use the same map provider, you first extract the map , send it to the map provider along with the ecu details (in this case they did the latter) and they make the required checks and send back a modified file which is then written to the customers ecu, there is a still a licence fee which is usually done in credits, eg you might buy 12 credits for £1000 allowing 12 remaps.

You can see why there are plenty "bloke with a laptop" type people doing them , its good money if you do the volume and don't have premises

Those companies that have a dyno may offer a before and after graph and the good ones monitor air fuel ratio and knock just to check, but few will have the ability to alter the map, typically the car is road tested as well , these are the maps that typically cost around £300, many people think dyno run=custom map but that's rarely the case, and many companies mislead the customer into thinking this. It often takes longer to strap the car on the dyno than it does to change the map

Even if the mapper can custom map the car doesn't mean they will , an experienced mapper may well have done that model many times so will often have a custom file saved on their laptop which they will flash and tweak to suit the particular modifications on that car

So whether its custom or generic makes little difference the important thing is the knowledge and experience of the person doing the work, in this case the tuner appears to know their stuff but the map supplier made a mistake in the file they sent




For the OP , I suspect 50 miles is not enough so things may settle down with any luck

[hedges88]

stevieturbo said:

You will never "optimise" anything...with a generic blind remap.

And your fuel trims now are not after a remap as such....as allegedly it has been put back to standard. Although standard for what....is harder to say.

Your best bet now might be to see if you can get another ecu from the same car that has not been tampered with, and see if you can have it programmed to your car/immobiliser or whatever it needs.

Then for a faster car....buy a faster car.

This is just it though, even the biggest names in remapping with the best reviews will tell you that it's not generic/blind.

Somewhere a donor car was supposed to have achieved those figures on a rolling road by altering the factory map. I don't think a professional remap company would ruin their reputation or break trading standards rules by applying a map file that had not actually been tried and tested first?

I could I guess technically purchased that map file myself for half the cost and applied it myself. If it had gone wrong and I bricked or messed up my ECU there would be no one to blame but myself. These guys did do all the right things, making sure the battery and interface voltage were stable. I was even told to turn off my phone's Bluetooth so a phone call would not be routed to the head unit and draw power. They had some equipment I know to be very very expensive and didn't take any shortcuts. Yes they have obtained a map file already generated but that's what ANY of even the biggest names in mapping are going to do. No one is going to want to spend time extracting the map like this: https://youtu.be/GC2ZsATXQ_Y and then spending time improving the map on an unmodified N/A car.

Let's not forget that these off the shelf maps are often totally fine with turbo motors, BMW 116D is easily remapped to BMW 118D power if not more and that can net good results without each car having hours spent customising individual rolling road maps. A custom map would be better yes, but the "generic" ones often work just fine, bluefin boxes etc are generic. Being a naturally aspirated petrol should NOT make a difference, if the map file was done correctly and tested then there should be no problem. You accept that your car and the donor car may have different wear and mileage and that you're end result can't be a cast iron guarantee. It should not however cause a complete systems failure and serious faults immediatly after the flash

[hedges88]

liner33 said:

I think there is a lot of confusion in vehicle mapping/remapping.

A custom map is expensive, itro £600+ why? because it takes a decent amount of time and usually a licence fee depending on ecu/model

Most remaps are generic, originally the map was custom written on a car on a dyno but then is repeated on many cars, provided your car is in good condition there is next to no risk and they work well.

A lot if not most companies use the same map provider, you first extract the map , send it to the map provider along with the ecu details (in this case they did the latter) and they make the required checks and send back a modified file which is then written to the customers ecu, there is a still a licence fee which is usually done in credits, eg you might buy 12 credits for £1000 allowing 12 remaps.

You can see why there are plenty "bloke with a laptop" type people doing them , its good money if you do the volume and don't have premises

Those companies that have a dyno may offer a before and after graph and the good ones monitor air fuel ratio and knock just to check, but few will have the ability to alter the map, typically the car is road tested as well , these are the maps that typically cost around £300, many people think dyno run=custom map but that's rarely the case, and many companies mislead the customer into thinking this. It often takes longer to strap the car on the dyno than it does to change the map

Even if the mapper can custom map the car doesn't mean they will , an experienced mapper may well have done that model many times so will often have a custom file saved on their laptop which they will flash and tweak to suit the particular modifications on that car

So whether its custom or generic makes little difference the important thing is the knowledge and experience of the person doing the work, in this case the tuner appears to know their stuff but the map supplier made a mistake in the file they sent




For the OP , I suspect 50 miles is not enough so things may settle down with any luck

Hopefully yes I'm waiting to see if it will settle down. I'm hoping someone experienced enough with Mercedes-Benz DAS/XENTRY etc can confirm what was likely done to get the car working again? One thought that popped into my head, is it possible the fuel map they wrote is still there somehow and just the ME-SFI control module was just flashed? Can it's fuel map exist independently of the motor control system or are they most certainly one and the same and tied together?

I need to learn an awful lot more about mapping, fuel trims and everything it's just a huge amount to take in. My understanding of the video I posted is that the ECU is extending injector duration because it think's it's running too lean? Then when I've revved it up and the values go as high as 19.5 it must think the exhaust gases are indicating a very lean condition? Yet no symptoms of lean running are present. It drives well without pausing or hesitating, starts well and idles smoothly. Is this lack of problems ONLY because of the work it is is doing to correct the mixture? if it were prevented from making changes I would experience lean running symptoms.

I'm wondering if it would be useful to unplug the MAP sensor and see how the engine behaves in it's "assume the worst" conditions? My fear is that the software that's been flashed to it may have any number of differences or revisions, for example the MAP sensor may have been altered sometime during the production and the ECU thinks it's working with different hardware than it actually has.

[stevieturbo]

hedges88 said:

This is just it though, even the biggest names in remapping with the best reviews will tell you that it's not generic/blind.

If it is not done on your actual vehicle, testing, adjust, repeat....then it is generic.

Some generic files will be better than others, but it's still generic.

[stevieturbo]

hedges88 said:

I don't think a professional remap company would ruin their reputation or break trading standards rules by applying a map file that had not actually been tried and tested first?

I would not consider the vast majority of people loading files into peoples cars as "professional"

There may be a handful of proper tuners though.