Poor MPG...

[callum]

Well, we were expecting it to be bad, but it really is cruddy (diesel).
We went from spending £40 a month on fuel in our previous car, to close to £80 in the van, only getting 400km out of a tank.
I worked it out at around 23mpg around town, got it to 27 by doing a long run, but really disappointing. We have changed filters, cleaned the bango, oil change, tyre pressures. I drive like an old lady, very light footed and stixk to 55 on the motorway (to my wifes annoyance!).

So...we took drastic measures and bought another car...
We bought a Suzuki Alto to run alongside the van as it was cost effective to run two vehicles. Certainly not selling the van!

But in truth, i was hoping for a smidge more from the van, thought it should break the 30mpg mark on a run, but no

[scanner]

That isn't really much out of the normal the only time I get much over 30MPG is on a very long run without much traffic and few stops and starts. It is accelerating back up to speed again after a stop that really kills MPG.

My answer is to run it a rapeseed oil/diesel mix I'm still running 50/50 and that works out at 75p/litre which ups my notional MPG to the mid-30's compared to running on just diesel at around £1.00 litre.

[Bongoplod]

Yep,agree with Scanner,both 2.5 diesels I owned did similar mpg on local and long runs.

If it makes you feel any better,after 2 diesels,I bought a 2lt petrol........18-20 mpg local and 27-30 on a m/way run.

So,yours is good!!

Brian

[cmm303]

Agree with the above replies. Your mpg seems reasonable. I have scraped a 30mpg with a 100% 50-55 mph run, using cruise control and Millers additives. Personally, I find this speed tedious so normally settle for 55-60mph (actual speed, indicated is higher) and this is reflected in my fuel stats! I have also managed high 20s on clear A roads, coasting up to junctions and creeping away from them. Looking back I think 3/4 of my refuels cover at least 10-20% town driving and we know this is Bongo's nemesis.

There are some reporting a bit better mpg and then there are few (Bongobongo123 comes to mind, sorry mate!) who are in a different league altogether talking about 40mpg. I could only get near that if I pushed Bongo half the way. I think these Bongos secretly use fairy dust or a magic carpet

Bongo is for enjoyment so I tell myself not to get hung up about mpg. It is what it is!
http://www.fuelly.com/car/mazda/bongo/1 ... /fuelchart

[helen&tony]

Hi
My journeys are about 20 Km. minimum, and often longer, and the speed on average around 30 in villages, to 40- 55 on open stretches. Taken over around a 6 month period logging every tankful it turned out a good 29- 32 MPG...which is what others seem to get when you increase my speeds to what the others quote...so I'd say 30 MPG is pretty average, and hardly uneconomical . I merely checked ours to see what the local fuel gives, as quality varies immensely.
In the end, a big lump like the Bongo is not a good choice for the fuel misers...and it's probably one of the more economical cars I've owned , with 2 exceptions
Cheers
Helen

[BongoBongo123]

To quote Scanner: "It is accelerating back up to speed again after a stop that really kills MPG."

This is very true and the more slow and smooth you accelerate the better. (Not always practical with a bright white LED Merc impatient revving up behind you !)

To drive economically actually takes a bit of practice. A good rule of thumb is the more you are pushing the pedal the more fuel you are using. Be mindful of that, gently does it. Around town is not going to provide good mileage in a Bongo mine is pretty dire too, I have never measured it though as I do not do much in the way of local journeys. i.e., short 5 mile ones.

I listen to my engine, high revs = more consumption, be smooth accelerating, reading the road ahead to not brake when it is not necessary.

When I am up to speed on a motorway I listen to my engine sound, there is a speed around 50mph-55mph where there is this sweet spot where the engine/gearbox makes minimum noise, this must mean minimum friction and a mechanical balance/equilibrium. THIS IS THE ECOSPOT !

Try and reside in this smooth state for as long as possible on a big A road or M way. It is almost like a point where there is a perfect balance of revs vs momentum or throttle depression vs speed. That's the only way I can explain it.

Of course you cannot sit there forever as there are of course inclines / road events but you judge these in advance from watching the road and make smooth relaxed compensations on the throttle minimizing the need for abrupt speed changes.

Pull out things I do not need to carry about, tyre pressures (tyre types), no aircon or windows open at relevant times, always empty water tank when not going to be used. Above all think :

SMOOTH

I feel like a broken record sometimes but :

Given the amount you are spending on diesel it could well be worth trying:

1 Can of BG244 in your diesel tank ( a 1 use per year cleaner)

http://www.amazon.co.uk/BG244-DIESEL-FU ... B0062KYGZC

BG 244: Fuel System Cleaner designed for Diesel £21.99 on Ebay

And then add Millers diesel Power Ecomax additive to subsequent tanks (you can put a double dose in as well as per instructions if you wish) after that (Millers is a regular use diesel fuel additive/cetane booster and fuel line/injector/lubricant/ cleaner)

http://www.millersoils.co.uk/automotive ... sector=Car

http://www.ebay.co.uk/itm/Millers-Diese ... Sw8-tWVY4d

Unless my meter is inaccurate (and I have checked my mileage on google and it adds up correct as per the meter and my calcs within an acceptable couple of miles) I can with regularity get 40MPG on a 50-55mph (I can get high 30's even when stuck in jams for hours) run so getting only 27MPG which is about 35pct less seems a bit odd. I did my 43mpg record down the A303 going west from the M25. I do a rough calc using brim technique every now and then and 40mpg is pretty much standard on a long run.

(Did you do air filter as well? That's a fuel economy biggy)

People on seem to achieve 27-35mpg on long runs from what I have read.

I don't know if mileage (or km-age in the case of a Bongo makes a very big difference) but mine has only done 148,000kms - 91,000 miles. That could well be going in it's favour as that is very low mileage for it's 20 year age and the engine will not have worn that much as long as the servicing has been ok.

I have to say I rate the products I have mentioned above highly. Both the one off/occasional use BG244 diesel fuel system cleaner and the Millers. It cleans any deposits from the fuel lines, injectors, intakes, valves etc. and as I gather these deposits can right royally screw fuel efficiency and power up.

How many miles has yours done ? If it has never had a BG244 then that really must be worth a go. FWIW other than the rare problem start I have had which has not been seen for a long while) My exhaust to the eye is clear as air itself. No soot at all, nothing, even after just 2 mins idle when it is not warmed up even. I think I got a good engine.

[callum]

hey, thanks for the replies.

I have learnt to drive sensibly over the years having had many classic cars, so steady driving is something i am used to (obviously not in the first couple of years driving when i was a fool!).

I did indeed do the air filter too. The last piece of my puzzle is to replace the exhaust, the tail piece (after silencer) fell off before i bought it, so my father-in-law (who we bought it from), puttied on a replacement. I bought a stainless exhaust, just haven't got around to fitting it yet.
I also received my Millers additive in the post yesterday, which i shall be using.
Now we have the other car it isn't as much of an issue, but i still want to see what i can do to improve the situation.

[mikeonb4c]

hey, thanks for the replies.

I have learnt to drive sensibly over the years having had many classic cars, so steady driving is something i am used to (obviously not in the first couple of years driving when i was a fool!).

I did indeed do the air filter too. The last piece of my puzzle is to replace the exhaust, the tail piece (after silencer) fell off before i bought it, so my father-in-law (who we bought it from), puttied on a replacement. I bought a stainless exhaust, just haven't got around to fitting it yet.
I also received my Millers additive in the post yesterday, which i shall be using.
Now we have the other car it isn't as much of an issue, but i still want to see what i can do to improve the situation.

Your MPG figures sound about right. Is yours an 4WD or 2WD? You may find that on a long run on the open road taken at gentle speed you may get 30mpg+ but mainly, the trick is to factor in (lack of) depreciation and (hopefully) reliability and not too many big bills and then compare that with the alternatives, also putting in something for usefulness and the fun of having one. Generally though, buying a 2nd car to save on fuel costs is not likely to deliver a saving overall. Thinking more about what journeys you really need to make can be more relevant (for example, shop at supermarket etc or buy online). If you''re stuck with a lengthy daily commute then I can see fuel could start to be more of an issue.

[callum]

well, the van is/was used for my wife. Stay at home parent, and drives to see people. Once a week she does a 20 mile trip to my nans and incorporates the shopping trip into that (didn't before, but fuel costs meant we had to, no bad thing). I certainly would not be willing to suggest to her that she needs to cut down on seeing people due to fuel costs!

Fully understand where you are coming from regarding the second car. as it stands, due to having only classic cars for the last 8 years, i have no no claims benefit. When my wife does go back to work we will need 2 cars. I use a 125 motorbike for my commute as it's very economical in all senses.
We decided that as fuel costs are so much for the van, that it is prudent for us to start building up NCD on a policy that i use, for a very small car (Suzuki Alto), as MPG is excellent, tax is £30 and insurance is cheap. At the moment, the van insurance is over £600, adding me as a named driver on it put it up quite a bit plus the mileage we wanted because it was a daily driver.
So, the real savings will hopefully be next year when we drop the mileage right down, plus me as a named driver won't be so bad as i have my own car, so not seen as a problem by the insurance company AND i will have, hopefully, a years worth of NCD, which when doing a dummy check, reduced my insurance on the Alto by £100. So the savings will be very real!
Oh, the car only cost £250, so i will keep up the maintenance on it, i do all work myself so unless the mechanical side dies catastrophically, I'll hope to keep it on the road for a couple of years.
The difference in fuel cost will offset the Insurance and tax currently, so as long as i keep costs of maintenance down on the wee car, we'll be okay.

[mikeonb4c]

well, the van is/was used for my wife. Stay at home parent, and drives to see people. Once a week she does a 20 mile trip to my nans and incorporates the shopping trip into that (didn't before, but fuel costs meant we had to, no bad thing). I certainly would not be willing to suggest to her that she needs to cut down on seeing people due to fuel costs!

Fully understand where you are coming from regarding the second car. as it stands, due to having only classic cars for the last 8 years, i have no no claims benefit. When my wife does go back to work we will need 2 cars. I use a 125 motorbike for my commute as it's very economical in all senses.
We decided that as fuel costs are so much for the van, that it is prudent for us to start building up NCD on a policy that i use, for a very small car (Suzuki Alto), as MPG is excellent, tax is £30 and insurance is cheap. At the moment, the van insurance is over £600, adding me as a named driver on it put it up quite a bit plus the mileage we wanted because it was a daily driver.
So, the real savings will hopefully be next year when we drop the mileage right down, plus me as a named driver won't be so bad as i have my own car, so not seen as a problem by the insurance company AND i will have, hopefully, a years worth of NCD, which when doing a dummy check, reduced my insurance on the Alto by £100. So the savings will be very real!
Oh, the car only cost £250, so i will keep up the maintenance on it, i do all work myself so unless the mechanical side dies catastrophically, I'll hope to keep it on the road for a couple of years.
The difference in fuel cost will offset the Insurance and tax currently, so as long as i keep costs of maintenance down on the wee car, we'll be okay.

That all makes good sense plus you'll be able to enjoy the best of the Bongo and not the worst and you've got a new hobby.

[Northern Bongolow]

things i did to up my fuel mpg.
the first biggy is get it 4 wheel aligned, if its dragging a bad leg then its going to use more. .
then fitted the right tyres, harder compound 107/109 van tyres all new and of exactly the same age/size so the 4wdrive system is not fighting itself, went for fuel rated rather than wet/dry grip as im not in a sports car.
mines a manual box so i changed all the box and diff lubes for new oils.
removed the egr and opened up the crankcase breather to atmosphere, this gives the engine its best cool air to breathe.

dont really know what it does to the gallon, but its bloody good for a bongo.

[cmm303]

Any problem with adding BG244 with a trace of Millers in the tank?

[BongoBongo123]

Any problem with adding BG244 with a trace of Millers in the tank?

No expert on that but I would guess given you will be diluting a trace of Millers with 65 litres of diesel it will probably make absolutely no difference whatsoever.

The BG244 has a cetane boost in it as well, but the detergents and solvents have much greater concentration than the Millers "every tank" treatment. I have done BG244 only once after I got the Bongo. If you use Millers from then on in every tank there will likely be no need to ever use BG244 ever again.

What I have read is with the BG244 (Diesel specific version) is that it helps if it can remain in the fuel lines etc. for a longer period as opposed to a shorter period. (Presumably it remains in contact with injectors, valves, other components, and fuel lines for longer thus penetrating and doing a deeper cleansing job) So doing 50 miles a week for 5-6 weeks would be better than filling up and doing a 400 mile run all in one day. In any event I have never read a bad thing about BG products with some older vehicle users reporting especially good results in performance, idle smoothness, starting and economy.

Of course practical usage of your Bongo will determine how long it can remain in the system. I just bunged it in and used a full tank over about 2-3 weeks at the time, just after I got the Bongo. I always do it with cars I get. I did it with a petrol (BG44k Petrol) car my dad handed down to me (17 years old as well and running sweet)

Next job for me coming up in next weeks is Magnatec oil change, been in 11 months now but I have only done 3,500 miles max.

[cmm303]

Excellent. Thanks BB123. No specific Bongo expeditions planned for a while so good opportunity to pop it in and do occasional local trips, like for its MOT

[BongoBongo123]

Myself, I would run the BG44K/BG244 before the MOT and not during if I could control my mileage in that timescale (use of other vehicle or not etc.). I do not know what effects the actual product could have on emissions whilst being burnt.

Probably almost none at a guess but it might be best to be certain.