my V6 seems to be using a lot of fuel

[bullyroberts]

I have hadmy v6 bongo for 5 years now and it has always seemed a bit thirsty but i thought that it was because it was a v6 but the lsst 3 years it has struggled to get through the mot because of emissions, i have had a new cat fitted and that has not helped much so i have worked out my mpg and it turns out that it is only doing 11.5 miles to the gallon, when it is idling it relly smells of petrol, has anyone got any ideas what i could do, i am thinking of getting a garage to do a diagnostic on it

[Gasy]

Get it converted to LPG
Someone will be along soon with info on v6
Think Someone had his set up via diagnostics on here when they had it LPG
Seem to remember it was a bit of a pain ended up with having to do to while driving and garage bloke in passenger seat with laptop plugged in and running as driving it
But that was for LPG
He will be along soon

Have you checked for fuel leaks

[weebrian]

I get an average of 20 mpg on petrol and have done consistently for the last four years so there is definitely something wrong with your motor. Even running on LPG I get close to this so can only imagine a leak or a very poor tuneup. I'm sure someone will be along to offer specific reasons for this.
Good luck.

[Simon Jones]

Gasy was right: it was me that had the V6 tuned by the chap with the laptop whilst I drove it, but that was just the LPG system as it ran like poo after it has been tuned based purely on emissions. That unfortunately wont help in your case as you don't have LPG.

I think you need to get to the bottom of the problem as it could be ignition/timing/induction/exhaust related which wont go away just by adding an LPG conversion. Can you post up your emissions figures from your last MOT so we can compare notes? I had mine MOT'ed a few months back and intentionally switched it back to petrol and it only just sneaked thru as the lambda reading was right on the upper limit while all the others like CO2 were well within the limits.

A few possible things that can contribute to my high readings are tiny hole in the exhaust or dodgy lambda sensor. I've checked the exhaust visually and it's fine, and I've seen the lambda sensor readings from the LPG diagnostics and it was going up and down as expected. As it's currently running fine, I'm going to leave it there for now.

So, my suggestions are:

Check / replace air filter
Replace fuel filter
Check / replace spark plugs
Consider replacing distributor arm, cap and HT leads (not cheap)
Check ignition timing. I've yet to fully get my head round this yet as it involves shorting pins in the diagnostic sockets before getting the stobe going. I'm going to have a crack at this presently so will pst my findings
Other things to consider: check/change ATF in the gearbox and check the brakes are not binding.

I don't have my exact consumption figures to hand, but I think it's 21/22 on petrol and 16-19 on gas.

[g8dhe]

Yup check all that Simon suggests above we've averaged 21mpg except when the spark plug connector/lead developed problems once down on Dartmoor in Sept 2013;

A while after that I replaced all the leads as it still hadn't recovered completely, and that has started to bring the average back up again.

[Jim the Box]

As said previously 11 mpg is not normal, if I drive very carefully I can get 23 mpg on petrol and
20 mpg using LPG, with my V6 so something is not right.

[bullyroberts]

Thanks for all the replies so at least I now know that I have a problem, i will start by changing the air filter as I have never done that, to be honest I have been pretty lazy with stuff like that since I have had my bongo but I had already decided to spend a bit more time and money on it this year.
Also I have a friend who has got a diagnostic machine and he has said he will put it on my bongo so hopefully that might help
i will post back once I find anything else out about why my mpg is so bad
once again thanks for all the advice ☺

[BongoBongo123]

I would go:

Air filter (can definitely affect MPG significantly)
New spark plugs
New plug leads if never changed
How is your coil ? (I wonder if then tend to just go or if they can progressively produce weaker spark?)
Oil change (did you know mpg and performance goes up a small amount with fresh oil?)
Oil filter change

(Edit : Simon giving good advice in his post as well)

Can of BG44K in your full petrol tank (cleans fuel system, fuel lines, injectors, valves and piston heads) Typically on an engine never been treated you can see 2-3 MPG increase. BG44K is a high potency "one off" cleaner that is best used once a year or every 2 years to blast deposits off.

I also use Millers standard fuel additives in every tank and I rate it highly. (Much cheaper than the BK 44K at £10.00 bottle treats 10 full tanks of fuel)

http://www.ebay.co.uk/itm/GENUINE-BG44K ... 56644ce417

Millers increased slightly as a testament to how many people are using it:

http://www.ebay.co.uk/itm/Millers-Oils- ... 2ec7857ff7

Then tune up (without any additives in the tank). No point doing a tune up if the engine is heavily coated in combustion products it will never run particularly well and you might waste money on having to re-tune again once said combustion products have been cleaned out.

Your emissions will also improve

Good luck with the MPG I am sure you can get it upped without too much bother.

[bullyroberts]

Thanks for the advice I have bought a new air filter today and I have ordered a can of bg44k and the millers fuel additive so hopefully that will help bring it a bit closer to where it should be, also a friend mentioned that he thought it might be the lambda sensor has anyone ever had to change there's if so any advice would be appreciated ☺
if all else fails I will change the ht leads but they are quite expensive so it's a last resort

[g8dhe]

You say at the start that there is a very strong petrol smell, this would suggest that there is a LOT of unburnt fuel, which is again symptomatic of poor spark, I would take a look at your leads and spark plug connectors for damage;

Its quick and costs nothing to look first!

[Simon Jones]

Also check all the rubber petrol hoses for signs of leaks. There's a feed and return to the injector rail.

http://lushprojects.com/bongopartsmk2/c ... mgno=.html

[bullyroberts]

Thanks again for the advice i am going to fit the new air filter at the weekend so I will check the leads and hoses then

[BongoBongo123]

My mate is always talking about spark leads, when you think of the kind of stress they put up with, 10s of millions (100's) of high voltage sparks. They can get somewhat corroded with a powdery corrosion forming over the years. When he changed his which were only 7 years old (with the original Ford versions) he was convinced he noticed it.

A tip for the BG44K try and put that in when you know the fuel might be in there for a while i.e. not just before a 300mile straight journey (which will burn the entire tank in 5-6 hours), that way it lies in the fuel lines and injectors etc. for longer doing a more thorough job. And also ideally but not strictly necessary just before an oil change and definitely before your mate does the timing/tune up job for you, that's a good buddy to know there !

The Millers is dead easy measure 1 measure out and pop it in the tank and it goes without saying not to use them at the same time.

When I pulled my air filter out from the previous owner I saw it had a deep black sooty mark where the air was sucking through so I knew that was going to help significantly when I changed it. I reckon when I got it I was 20-25pct down on the mileage I get now after all the servicing I did. very nice feeling when the Bongo is running smooth an efficiently.

Good luck interested to see if all this gets the mileage up.

[bullyroberts]

I have changed the air filter today and put in the BG44K so i will see how that works, it might be a few weeks before I will be able to check the mpg as I don't do too many miles each week also when I changed the filter it looked pretty good considering I have never changed it before
does anyone know of any websites that sell lambda sensor for bongos as i was talking to someone who said they had a similar problem and it turned out to be his lambda sensor,I have had a quick look but they seem quite hard to find
Does anybody know what the part number is for a replacement lambda sensor
cheers

[Simon Jones]

You can get a pattern part for £40 and I'll have to try to dig up the details of where it came from. It's a two wire type and you need to cut the existing connector off and attach to the wires on the new one. I've not fitted mine yet and am in two minds as it may mess up the LPG tuning which took some fettling to get right.