5th Injector Mod & Ecu Update

[Matus]

As I mentioned last month I went through the recall process. Got the new 5th injector - although I've never had a problem or limp mode, and the consumption was very good.

As first I've noticed change in the idling. I am still not sure how exactly it is now, but my observation is: it still idles at 1100 till the operation temperature is reached, however if I stop the car, for example for 2 hours, the temperature decreases to 1/5, but now it idles all the time at 800 - even when the operation temperature is not reached.

Second observation is the consumption. I know it is too soon to have final verdict after one tank, but I have mention that. This tank I was driving in the city more than ever. Usually I drive (urban-extra urban-higway) 20%-40%-40%, but this time it was 40-50-10. Already the BC indicated optimistic number (6,8l/100km;41,5mpg) - I expected worse numbers after so much of urban driving.

To my surprise, after refuelling and real calculation the consumption is 6,56l/100km (43mpg) - my best consumption since september 2007!

[Scarlet Pimpernell]

Mine has really shown no change at all. Sorry if some of you think "Here he goes again" so please move onto the next post in this thread if it depresses...

I don't think that the new 5th Injector will improve MPG. I think it's redesigned to work better with the new pipes/ECU so it won't clog up and cause a limp mode. If they change the fundamntals of the ECU and it's operations, the Co2 etc will be affected and I rckon it would need a re-classification. This is why some have suggested that there is a newer variant on the way.

The ECU is a strange one. Before the ECU mod and new pipes, I was getting low 20's in town, and high 30's at best overall on a run. Now I'm getting high 20' in town, and very very inconsistent figures on a run. Some days I get mid 30', other days low 40's on an identical run...what is for sure though is that the car has become very sluggish again over the last week...I almost have to stand on the accelerator - and no doubt this is killing the fuel economy! I have tried to drive it gently and had 2 close calls with an Van and Taxi almost hitting me at a junction, and numerous bleeps from behind as people think I'm driving too slow, including single finger salutes and gestures.

I actually almost bit the bullet and bought some DPS4 from Halfords (£11.99). I read the bottle, and it stated that you could get up to 7% improvement in fuel consumption and up to 4 extra cetane - which incidentally is similar to som claims from Oil companies about premium diesel. From what I gather users of DPS4 in a 220d are getting up to 30% better fuel economy than I am, and so I put the bottle down again...the gap is too great and smacks of something else not being right in the car! I don't just want to burn away even more cash...

It looks as though I will perservere with the dealership for a while longer and book it in again (yet again) as and when work allows. My patience is wearing very thin now...the penultimate straw will be DPS4 and the final one will be a new car (which I'm now saving up for again - 3.5 years ahead of schedule...).

[FinLex]

I may have been too quick to declare the 5th injector change meaningless what comes to fuel economy. Now that the weather is warmer and I've changed to my summer tires, it seems to return a bit better mpg figures than last summer. Early on the current tank, the board computer was at best showing tank avg of 5.3 litres per 100 km, that's 53.3 mpg! Now, half way through the tank, it's showing 5.6 which translates to 50.4 mpg.

One thing that's getting more and more obvious is that the mileage depends heavily on the engine temp. The first 10 to 15 minutes after the start, the consumption is radically worse. I remember that someone thought this was because of the higher idling revs, but I think that's more of a cure than a cause. On my usual daily trip I hardly idle at all and still get a huge drop in the mileage after a cold start. I think the high idling is there not only to get the emissions down but also to get the engine itself faster to its normal working temperature where it returns better mileage. So it could be a way to improve mileage rather than a reason why it is so bad after a cold start.

[Scarlet Pimpernell]

Finlex - I've also found this in the past. The idling is I'm sure too is to do with warming up the engine and the cat to bring down the emissions.

Strangely, as I started to take the car out my garage today, it immediately idled at 1200RPM. By the time the car was out of the garage, the idle dropped to 800. It's never behaved like that before as far as I have noticed - almost like a Petrol car with Auto choke.

Normally it would start at 800rpm, then the AC fan would come on after 2-5 minutes, and the idle would go up to 1200 until the temp needle was almost on normal. Today it was different. May be it's to do with the warm weather....who knows...

[Matus]

Jamboo, when did you have last time changed the air filter?

[Scarlet Pimpernell]

March - 20k service

[jalfa]

March - 20k service

well you don´t have to be a rocket scientist to figure out that there is something fundamental wrong with your specific car. I would have given up long time ago.

I get around 0.75 - 0.82 l/10 km´s (motorway) but then I drive constantly at around 110 - 150 km/h on my way to work monday and home thursday (300 km run one way). I´m not happy with that - I could probably lower that significantly if I drive within speed limits? but it´s just so plain boring I will have the car in for it´s first service in a couple of weeks and then they will recalibrate ECU and perhaps change 5th inj. I´m curious to see what happens with my mpg but my expectations is not that high. It would be great to see around 0.6 but I have picked my car for other reasons then fuel economy and is very happy with it.

[dgman]

March - 20k service

did you have the air filter replaced at your request, as this is not a service item until 40k.

[Scarlet Pimpernell]

March - 20k service

did you have the air filter replaced at your request, as this is not a service item until 40k.

No - I thought it was included...better check it!!

How do you get those darn butterfly clips of the engine covers??? I turned them and they looses, but other yanking off I can't how they come off...

[Matus]

press the small cap in the middle. Then just take it out (no turning)

[Scarlet Pimpernell]

press the small cap in the middle. Then just take it out (no turning)

Thanks...

[Matus]

my before last tank averaged 6,52 (43,3mpg) which is again lowest since october 07.

My last tank is interesting, as I had to do quick 320km return trip to go for my father (unforunately he smashed his uninsured e-class)

On the way there I went 70kph in urban areas, 100 extraurban and at highway and speedway (total app. 120km) the full throttle - btw it goes quite nicely till 180kph (113mph), to 210 (130mph) it goes slowly - I am not sure if I would hit the manufacturer indicated maximum.

At 180kph the consumption is 9.3 (30mpg) - I find this OK. The total average was 104kph and 7,2l/100km (65mph and 39.2mpg) - I think the consumption is OK.

Now interesting - on the way back I let my father to drive. Normally he drives his e400cdi automatic, so he is not used to manual. He tend to forgot to change the gears :) 120kph (75mph) on 3rd and 145 (90mph) on 5th were quite usual :)

He drove differently - on the higway he went only 145kph but extra urban 100-130kph (60-80mph)

His average at the end was 124kph (!!) and 6,9 (41mpg) - I find this fantastic, because he is not used to this car at all and 41mpg is good number for such a conditions.