High Fuel Consumption?

[antil33t 90]

Be happy... In the V8 I managed a thirsty 19.53L/100KM since the last fill. Admittedly, I have been very heavy footed but the $/fun ratio has been excellent!!

My E34 gets about that... OBC Says 20.2L/100km..

And it's not fun or fast, it's a slow boring barge LOL.

I should seriously stop using it for really short trips without it being properly warmed...

[Allanw 1071]

I wonder how some people manage these consumption figures.......

what Fuel are you running it on ?......

Yours does sound very similar to our M54 525i. We always use 95. they are not desinged for 91 at all (95 is marginal too). We don't get great milage, as it's generally either in town, or the drive home. The drive home has 4kms of country road, but it's very hilly and up down, and lots of bends. There is no cruising, though the manual trans must help a little. The traffic is a bit easier here too.

It also depends if you are using the OBC figures, or real figures too.

The OBC tends to vary car to car, but a lot report them being rather optimistic. Ours is very accurate - seems to be within about 0.2 L/100kms compared to the actuals I get on Fuelly.

[jeffbebe 1559]

WHICH Prompts the obvious question : what Fuel are you running it on ?

I always run 98 and use actual consumption figures not OBC which is always optimistic in the cars I've owned. 540 consumption is high because I'm having fun. 528 consumption was high because my average speed over 18 months was 24km/h and it got driven cold s lot over short distances. On a decent trip consumption would be in the 8L/100 range.

[str8_6 275]

get it scanned. Hopefully that should tell you something.

But from memory the ECU uses inputs from the MAF & 02 sensors to trim fuel maps. But anything from old spark plugs or crap fuel could affect.

But you are right. I regularly get 10l/100 in my M5 cruisin @ 100kph on the motorway, 14-15 on average when i hammer it and usually 600km out of a tank.

I'm getting the same consumption out of my M5. One of the things that pleasantly surprised me was it's economy on a long cruise. Generally around town it sits at 13 to 14 litres per 100km. Not bad really.

Little bit surprised by the 530i's consumption though.

[M5V8 337]

one of the reasons I'm really not keen to change.

The V8 is really not working hard at all at 100-120km/hr so it's consumption is really surprising for such a large heavy car.

I doubt you would realistically get that even in the new F10 M5.

I've seen as low as 9/100 hypermilling on the way back down from Taupo. Couldn't quite make it to 8 tho.

Edited June 19, 2013 by M5V8

[kingkarl 136]

After replacing the thermostat on my e34 I'm still getting 18.2l/100km

My commute is a 16km in Auckland traffic.... It's slow... but far from stop start.

I'm booking it in for a scan/vacuum leak check. Fingers crossed they find something wrong with it. If not I'm going to have to invest in a small-medium sized oil rig

[jeffbebe 1559]

After replacing the thermostat on my e34 I'm still getting 18.2l/100km

My commute is a 16km in Auckland traffic.... It's slow... but far from stop start.

I'm booking it in for a scan/vacuum leak check. Fingers crossed they find something wrong with it. If not I'm going to have to invest in a small-medium sized oil rig

My E39 528i was much of a muchness, in slow moving traffic would rarely be under 15L/100 and often higher but great on the open road (8-9L/100). I fixed just about everything I could except the Vanos seals. Ray's (HellBM) has just done double Vanos procedure on my 540i and the difference in fuel consumption is night and day. It was sucking down fuel at 20-25L/100 when driving short distances from cold and rarely managing better than 15L/100 on the open road. It's no getting 15-18L/100 around town and around 9-10L/100 on longer trips.

Vanos procedure isn't cheap though unless you do it yourself so I'd definitely rule out other options first through scan and smoke test, etc.

[_Matt_ 42]

I get 14.5/100km all city driving in my 535i e34 on 98

And

18.5/100km all city driving on 95.

Haven't tried 91 yet haha. 95 and 98 has a pretty noticeable performance difference too.

[lord_jagganath 421]

I'm getting around 12-14l/100kms in my mixed driving, 33 km commute with 15kms of highway running. would like to see 9l/100kms but that may just be a pipedream. Running 91 though.

Edited September 17, 2013 by The Juggernaut

[cliffdunedin 8]

I'm getting about 12-14kms around town and about 10ish open road from the e39, little sluggish under the 3k rpm so will look at doing Vanos soon and about the same around town from the e36.. but open road prob 7-9ish.

[Arma 134]

Have moved to the city since my thermostat was replaced. Getting between 15-16.5L/100km at the moment, with the majority of it being short commutes inside the city - sometimes after cold start. I always use 98.

[allan 295]

Would have to agree with Ron my 530 even in town was around 10l /100 and less on the highway. Get it checked out have the thing fully scanned ( by someone that knows what to look for) and stick a tube up the exhaust to check the exhaust gases. Just out of interest what transmission, final drive ratio do you have?

[Lucan 196]

I regularly reset my obc fuel usage thing and average 11.2l/100 in my 530i

Mainly city driving

[jeffbebe 1559]

Best to check genuine consumption... The OBC is not always accurate. I found in my 528i that actual consumption was better than that stated by the OBC - particularly when using quality fuel (98).

[qube 3570]

Arma:

My 330i (m54b30 same engine as your car) gets about 500kms to 55L of fuel. That's with a lot of cold starts at 6:30am and mainly city driving too. I drive on D most of the time and hardly ever push it hard. Even if I drive it hard I still get 450kms which at 55L puts consumption at 12.2k/100. Long distance trips got me about 650-700kms out of the full tank. I know it won't be the same since your e39 must be a bit heavier but I found that this engine was less thirsty than the m52b28tu I had in my old 328ci.

[kingkarl 136]

I Cleaned the ICV out today. What a huge difference that has made - car is running the best it has since I've owned it. In doing so I also managed to identify 2-3 serious vaccuum leaks that will explain the fuel consumption.... so time well spent.

The ICV clean took much less time than I expected so I went and bought some new plugs to occupy the rest of the afternoon.

I somehow managed to break one of the coil pack connectors.... so now the old girl is running the worst it has since I've owned it. That also means I have to take the train to work for the next few days until I can get it running on 6 cylinders again

Will be interesting to see if the cleaner ICV does anything for fuel consumption or if that will only improve when I get the hoses/intake replaced

[EuroSurgeon 2]

I have a E60 530i, I found car lacking torque for a while, let Ray do the vanos seals for me, I wont quote around town figures as my foot it made of lead

Auckland to New Plymouth, before seals 11.7l/100k

After seals 8.6l/100k

On way back from palmerston was hammering all way back, wont mention speeds 9.2l/100k

Before seals I have had car for 3 years, and never been below 10.6l/100k.

What lead me to seals was when car was cold, felt like full power,

By the time oil warmed up and thinned out torque seems minimal, I would have done myself but had better things to do so gave car to Ray and was very impressed

[kingkarl 136]

Obvious questions:

-What fuel are you using,

- what tyres & pressures do you run ?

Our E39 528 averaged 10.6 over the 298,000 km it had clocked up when we sold it:

- worst was 14.6 when booting the crap out of it

- best was 7.3 on a trip to Rotorua with the full family of 5 and all the crap including mountain bikes for a weekend of fun.

- Start stop stuff was around the 10.6 - 11.0 mark.

P.S. it was manual.

I only run 95. Tyres are Bridgestone Potenza G3 (predecessor to the re001 i believe) @ 34psi

I have the early m50 - so no vanos

Manual box does make a hugee difference - no doubt.

[aja540i 1906]

For that amount of fuel you could be running a v8!! Mine sits at 13.5 l/100k and thats a mix of town, open road and towing the trailer!!

Best ive had was 9.9 from Welly to Auck. I always use 98, sems to get better mileage.

[Allanw 1071]

For that amount of fuel you could be running a v8!! Mine sits at 13.5 l/100k and thats a mix of town, open road and towing the trailer!!

Best ive had was 9.9 from Welly to Auck. I always use 98, sems to get better mileage.

It could do better too. I've seen you drive

[aja540i 1906]

It could do better too. I've seen you drive

Bmw put 286 hp into it, it would be a shame not to use all of them!!

But, yes it could do better.

[kiwi535 538]

After replacing the thermostat on my e34 I'm still getting 18.2l/100km My commute is a 16km in Auckland traffic.... It's slow... but far from stop start. I'm booking it in for a scan/vacuum leak check. Fingers crossed they find something wrong with it. If not I'm going to have to invest in a small-medium sized oil rig

when i first bought my 535is it was a short auckland commute car the obc said 17 l 100.

[kingkarl 136]

I have Cleaned the ICV, replaced the sieve of an intake boot; replaced icv to manifold hose, new thermostat, new plugs and a brand new Bosch o2 sensor.

I'm Finally getting decent economy... 8.9l/100km open road which I am very happy about. $40 each way from Auckland to Tauranga.

The cheap fix I was hoping for didn't come to fruition (rarely does with euros right?). But it's good to have the car running right and the fixes will probably pay for themselves in fuel savings in 20-30k km time haha.

Next on the list is a suspension overhaul.... Fingers are crossed the jatco doesn't lunch itself in the meantime