W212 E350 not changing into 7th until 74MPH...?!

[Mancstar]

I think another person said it changes at about 60mph.... but please do check thank you

Defo changes to 7th at just over 60mph.

 

[ColinMerc]

I’m selling my e350 soon, my pride and joy and MB have ruined it with this so called update! 10mpg poorer, gearbox up and down through the gears, like sitting in a rowing boat, never into 7e unless I use flappy paddles. So frustrating

 

[Mancstar]

Why would they mess with the gear ratios!?

 

[TeddyRuxpin]

I guess there must be something about running the engine hotter/higher RPM that creates less NOx (at the expensive of higher CO2 and more fossil fuel burned)

 

[Mancstar]

I would have thought the opposite to be correct, in that a colder engine would produce less NOx? Obviously not I take it!

 

[TeddyRuxpin]

Me too, and this page seems to suggest that: Vehicle NOx emissions: The basics | International Council on Clean Transportation

I don't understand, but I expect it's probably a box-ticking 'hack' at the expensive of everything other than ticking the 'this car legally makes less NOx' box, much like the emissions scamming was in the first place.

 

[Bobby Dazzler]

Why would they mess with the gear ratios!?

The ratios are unchanged, they’re just changing the shift points, ie holding the gear long before shifting up.

 

[Jkh112]

This thread made me take note of when my E350 changes gear. In E mode it changed into 7th at 54mph. This is with the 7G+ box.
My service plan has expired and I was wondering whether or not to renew. Looks like I will be moving to an indie.

 

[Londonscottish]

I guess there must be something about running the engine hotter/higher RPM that creates less NOx (at the expensive of higher CO2 and more fossil fuel burned)

If you look at what a lot of the Germans did with diesels they frigged around with things so EGR's and DPFs didnt function properly or at all so NOx and particulates went through the roof. The tradeoff was better driveability and better fuel consumption.

If you make the emissions work in the manner they actually should ie in the way the authorities thought they worked all the time you're bound to take a hit, really.

There were enormous fines in the US for this. The manufacturers have got away Scott free over here.

Edit: VW fined $4.3bn, MB fined $1bn for same thing bu US authorities. Very naughty.

 

[merc07]

I put my C350 back to an earlier ecu version as it became undrivable with the over heating and high idle during its constant dpf regens.
I have been watching the soot levels using the icarsoft.
On short 25+25mile runs it would rise around 2g per day, a regen would activate above 5g or 250km sending the sensor temps to 800C.

I am now 3 days in with the earlier ecu and on the same runs I am at 1.8g BUT the level will drop while on a run without a regen where as with the updated ecu it would only always climb. Very strange ?

As for your 7th gear, that was the first thing I tried on Monday and I could not get it into 7 at 70 on the Motorway which due to half term was just 5 mins from my house. I assumed the engine was cold?
Or maybe it was not just an ecu update that was done - However, gear changes when cold have gone back to being VERY harsh, snappy - the update had cured this.

I will test gear 7 again today as I have a long run over the Mendips to do and by then it will definitely be warm...

 

[TeddyRuxpin]

How did you ‘put your c350 back to an earlier ecu version’?

 

[merc07]

I had a spare on an earlier version...swapped out the complete ecu..

 

[merc07]

Normal acceleration on the flat, it changed to 7th at 63mph every time.
I am up to 328km since a regen and the soot level went up by 0.3g....

 

[tonysmb]

This thread made me take note of when my E350 changes gear. In E mode it changed into 7th at 54mph. This is with the 7G+ box.
My service plan has expired and I was wondering whether or not to renew. Looks like I will be moving to an indie.

Mine has the 7g+ and having read various threads around this ecu update issue I virtually decided that I shall avoid MB servicing, particularly as there's mention of their service Ts & Cs being changed to include updates, effectively whether the customer likes it or not. Last time mine was serviced there had been talk of updates but it was before this latest 'recall' was mentioned. I spent some time making sure that they understood that I did not want any ecu/gearbox updates and their comment was along the lines that they 'do what the computer says'. There was no mention of updates on the ESS and nothing was done but my feeling now is that if the computer says 'yes', they'll now do it irrespective of what the owner wants.

 

[TeddyRuxpin]

I've even heard/read (from a cloudy source that I cannot remember) that when they plug the car into their computer it does the update automatically if required - however a member on this or another forum has said that they took their car in for a service and made the dealer 10000% sure that they didn't want the update, and apparently the dealer complied.

 

[TeddyRuxpin]

MPG decrease aside, I would love it if the damn gearbox would just go into 7th, even if it didn't save any fuel. It's just unnecessary wear and tear and a less calm ride. I might call Big Fish Tuning (who apparently did the maps for MSL) and ask if gear change points is something they can tweak with a tune. MSL said they weren't sure until they had the car in to remap (??)

 

[HAR51S]

Hi, not sure if this thread is still alive, but I also have this issue!
I’ve just done a 3500mile trip to Italy and back and noticed I was getting very frequent DPF regens. To the extent that, when they were not able to finish, I would get late up shifts and could smell burning when I got out of the car.
And now back in the UK, I would always stay in 6th gear at 70mph (1950rpm, not 1700rpm) and presumed that it was constantly trying to Regen. And as the OP says, 74mph or there abouts, it would still shift to 7th. I assumed that it gave up trying to Regen as I had taken the speed too high, being the reason for the up shift point, and not that the TCU maps were requesting it.

I am a powertrain (more on the Transmission side) Calibration/System engineer, so my brain was whirring as to what the reasons could be. My iCarSoft hasn’t been showing any codes recently, but I did get a DPF pressure code about 2000miles ago when I got restricted performance around Lake Annecy and had to pull in to check.
I also have some oscillation/jerky feel around 1000rpm 20-30mph, so after having the Trans oil changed assuming it was TC related, I assumed it could be high exhaust back pressure causing my combustion control to go a bit crazy…?

Yesterday I had “DPF-Fixer” come round to flush out my DPF. It was 95% (out of a possible 200%…) full, with 6g. The guy said it was fine and probably didn’t need it, but I thought maybe it was coked up with hard soot that couldn’t be shifted by the passive regen. He agreed, since the Ash level was low.
After doing it, his £800 Autel (i should have bought that one!) told him my DPF was empty; job done.

Last night I drove to Bham from Warwick and was hoping to get into 7th immediately, but nope! As the OP said, 74mph seems to be the 6-7 up shift point.

Now… I had the car serviced by Stuttgart Garage (good MB Indy in Pontypridd) in Jan 2022, just before my big trip. They did an A7 service with gearbox oil… not sure if they would have done any ECU flashing - suspect not.
I drove Cardiff to Dover at 70mph the whole way (44mpg) and was definitely around 1700rpm.
But half way through my Continental trip I noticed while sticking to the 110kph limits, I would be in 6th for ages. One time I let it continue for 45min and then all of a sudden it did a 6-7 shift. Happy days I thought, DPF regen has happened?
But then the next day it was again holding 6th.

Car has only been owned by me since Aug 2021, and is on 163k with Full MB history before.
I haven’t taken it to an MB dealer.

The only thing that has changed on the ECU is that super chips have worked their magic in November 2021. Would they have updated to something newer on the base SW? But then again it wasn’t immediately that I got this no 7th gear until 74mph issue. And also, I had frequent regens on motorway runs before the ECU flash.

Would be interesting to here other opinions!!

Phil

 

[FiveAlive]

Not changing into 7th until 74mph is a characteristic of the emissions update. However, I have found that if you accelerate harder up to speed, it will change into 7th before 70mph when you lift off. So sometimes you will see it go into 7th below 70, and most of the time it won't, regardless of DPF regeneration. To the best of my knowledge, during active DPF regeneration the engine is kept between 1500-2000rpm so there'd be no need to hang on to 6th gear at 70mph just for this. If you see 1500rpm when trundling along at 30mph on a level road, that's an indication of regenerating in progress.

I suspect that the 7th gear/74mph change was intended as a way to encourage passive regeneration, which is probably a good thing in itself.

 

[MrGreedy]

If the E350 OM642 engine has been plugged into the Merc hive mind since this thread was started (Jan 2020), then it will automatically apply any software updates. My understanding is the only sure fire way to avoid this is to not take the car to a main dealer.

Once it's been updated, EGR operation is significantly increased, increasing soot and require a lot more DPF regens.

As you've discovered, another aspect is holding on to gears more and not shifting up as early.

This is all focused on reducing NOx emissions (at the cost of soot and CO2 increases). Running the engine at higher revs and with more EGR operation reduces NOx)

 

[FiveAlive]

After the emissions update I saw a brief burst of DPF regenerations, and a couple of limp-ish mode incidents (no code stored, no EML, and returned to normal operation after an ignition cycle) after about 1000 miles and then again after another 1000 miles. But then my car settled down to normal again.... apart from the 7th gear/74mph thing and the mpg drop.

The frequency of DPF regenerations is dependent on driving style, of course, and I only use this car for non-urban journeys and usually with a bit of motorway driving thrown in, so it has a chance to keep the DPF clean unobtrusively and, I assume, passively as I don't see evidence of many active regenerations (I do keep an eye on the rev counter).