using too much fuel.

[Diagro]

Hey

so I'm seeing at most 26 MPG no matter how grandmaish I drive.

With a heavy foot it's 22 and below.

The timings are fine as they were checked again by garage, they spot on and I agree considering how the car performs.

Does anyone know what to check next? I don't think there is a fuel leak as I left it for 2 weeks on the drive over a sheet of ply and no marks were found on return at all.
I don't smell fuel when in engine bay when off or after a drive.

Not knowing much about how engines work I don't know what to check next to hopefully fine the cause and then find a solution.

I have read that injectors can dribble causing higher than normal fuel useage, could this be it? How do I check?

I can't afford to send this car back to the garage as I have spent a fortune on it and now need to save for the next time it has to go for repairs lol.


any help and guidance will be greatly appreciated.

Ta
james

 

[Daniel]

Fit some 14 inch wheels.

 

[Addicted]

Could be a faulty lambda sensor?

If you go 60mph on the motorway and reset mpg counter do you get over 40?

 

[Ex-User (19928)]

Fit some 14 inch wheels.

flol.

On a serious note, any fuel leaks wouldn't show a lower MPG on the computer, are you reading 26 on the computer or is that what you have worked out between fill ups? How's your maths?

 

[Diagro]

The computer shows higher MPG such as 35 to 40.

its at the pump I work it out.
My maths is fine

The lambda was replaced last month due to old one not reading correctly.

 

[johnbuck]

I was getting about 28mpg with gentle driving, found one of my front brake calipers was binding slightly.

Stripped, cleaned and re-greased all 4 calipers and can now get average 36 just running around rural roads without caning it.

 

[Matt W]

How many full tanks have you used to calculate it?

 

[Diagro]

I was getting about 28mpg with gentle driving, found one of my front brake calipers was binding slightly.

Stripped, cleaned and re-greased all 4 calipers and can now get average 36 just running around rural roads without caning it.

How do I check breaks? When car is up I can turn the wheels but they are not as loose as the wife's megane are and have a metal on metal sound.

How many full tanks have you used to calculate it?

4 to 5 mate. The absolute best I managed was 28.5mpg and worst was 19.7 lol.

that's on Momentum 99.

 

[Matt W]

That's pretty bad. Sure you're not using an american website to calculate it?

 

[Diagro]

No
its 4.5*L per gallon in UK. That's what I use

if you think it's bad you should have seen what it had before I had belts and dephaser done.

Used a whole tank in under 100 miles

 

[Addicted]

I'd say one thing is clear, something is FUCKED!

 

[Ex-User (19928)]

I was getting about 28mpg with gentle driving, found one of my front brake calipers was binding slightly.

Stripped, cleaned and re-greased all 4 calipers and can now get average 36 just running around rural roads without caning it.

You would notice that on the trip computer though.

Maybe you've got a fuel thief in the area that happens to have a Clio 2 key (opens all Clio 2 petrol caps).

 

[Fletcher]

I'd say one thing is clear, something is f**kED!

^^^^This TBH.

 

[Addicted]

Even pushing, I struggled to get under 250 miles a tank!

 

[Fletcher]

My 172 is only used for 'fun' miles and the MPG counter is currently reading 33mpg.

 

[Diagro]

Anyone got any ideas on what I can check? I am tempted to replace the plugs and injectors but not sure if they would help at all.

 

[johnbuck]

You mentioned that your brakes might not be right..........metal on metal certainly isn't good.

If they are sticking then that wouldn't help fuel consumption.

Easy to sort out if you know what you're doing, if not get, them checked, even the fast fit places do brakes now

 

[Ex-User (19928)]

If it was brakes then there wouldn't be a massive discrepancy between the OBC and actual fuel usage.

 

[Diagro]

You mentioned that your brakes might not be right..........metal on metal certainly isn't good.

If they are sticking then that wouldn't help fuel consumption.

Easy to sort out if you know what you're doing, if not get, them checked, even the fast fit places do brakes now

I am going to take them apart at end of week and see whats up. Gping to do it myself as cant afford to give money away to garages.

If it was brakes then there wouldn't be a massive discrepancy between the OBC and actual fuel usage.

Understandable. So must be something else.
Would the injectors be at fault? say if one was dribbling ?

 

[MartinR]

Here is an odd one for you. Mine used to show 28max on the computer. 6 months later the box gave up.

Had it rebuilt with the main shaft (s) replaced and all bearings. I refitted it and boom 33 minimum all the time.

Spoke with Martin at agency transmissions who rebuilt it and he said that the worn parts was most likely causing drag so fuel cunsumption was suffering.


Also if your alignment is out it will use more fuel. But as i have said in some of your previous threads its your timing i reckon its wrong regardless of what that garage has said

 

[BlakeTillz]

This is exactly my problem. Im seeing 27.8 normal driving. Just seems like its drinking fuel like its going out of fashion. Ive got a decat and the fuel smell is soo strong too. I think mines running really rich

 

[Diagro]

Here is an odd one for you. Mine used to show 28max on the computer. 6 months later the box gave up.

Had it rebuilt with the main shaft (s) replaced and all bearings. I refitted it and boom 33 minimum all the time.

Spoke with Martin at agency transmissions who rebuilt it and he said that the worn parts was most likely causing drag so fuel cunsumption was suffering.


Also if your alignment is out it will use more fuel. But as i have said in some of your previous threads its your timing i reckon its wrong regardless of what that garage has said

My gearbox does whine so may have a hand in it.

The garage were adamant that the timings are fine, no where close is able to test it apart from them.
There is a Renault garage in Coventrybut they want £95 just to check... No way

 

[Diagro]

This is exactly my problem. Im seeing 27.8 normal driving. Just seems like its drinking fuel like its going out of fashion. Ive got a decat and the fuel smell is soo strong too. I think mines running really rich

My exhaust gas smell of fuel...
how do we make it run leaner?

 

[MartinR]

Go to Fred up the road. He will tell you if its right or not and is cheap.

Im not one to use the timing card. But i reckon thats your problem mate.

 

[Diagro]

Ok chap.
can you tell me which company Fred works for? I will need to plan a trip to see him. And also to get a price from him

 

[Diagro]

Ah fred at BTM.
Will contact him now

 

[TheEvilGiraffe]

The computer shows higher MPG such as 35 to 40.

its at the pump I work it out.
My maths is fine .

Something is very wrong here. If you were ~5% different' I'd not be worried. 50% .. something's wrong.

The computer should know how much it's putting in per squirt .. so it should be pretty accurate.

Are you filling and calculating brim to brim ? I assume you are...

How many miles and how many litres are you using on average..........

 

[Diagro]

Yup till pump clicks. I use Same pump most of the time.

last tank did 280 miles before needing filling with 48L

 

[Fred@BTM]

Go to Fred up the road. He will tell you if its right or not and is cheap.

Im not one to use the timing card. But i reckon thats your problem mate.

I'm typing this whilst lying on the floor, got a bit dizzy for a second

 

[Dan@SJM]

I'm typing this whilst lying on the floor, got a bit dizzy for a second

 

[Chrisgti6]

Odometer fault perhaps? Under reading the miles driven?. Maybe use sat nav to calculate the miles of a journey and see if the odometer is the same.

 

[Diagro]

Yea it's reading the correct miles.
its 22m to work and that's what it reads

 

[scotty10]

what about a cts can that cause low mpg?

 

[Fred@BTM]

the acid test - get on the motorway (with the car warmed up) at 65mph and rest trip computer as you're driving, stick at 65mph for 10min and tell me what it reads, it should be around 44mpg, less than 40mpg and its broke (thermostat, CTS, timing, lambda etc)

 

[MartinR]

I'm typing this whilst lying on the floor, got a bit dizzy for a second

Shock horror

 

[Diagro]

Ok fred. Will do that today or tomorrow.

 

[Diagro]

Well.
Drove around a lot today. Car feels different from yesterday.
not sure what srs did lol.
much more snappy.. va va vrooooooom

in regards to fuel still testing.

would it help at all if I was to do the 10 mile @ 65 mph with the rs tuner logging stuff? If so what parameters should I log?

 

[Addicted]

Just don't normally, I suggested it on the first page, if its over 40mpg its normal I suspect it won't hit 40 tho.

 

[BlakeTillz]

the acid test - get on the motorway (with the car warmed up) at 65mph and rest trip computer as you're driving, stick at 65mph for 10min and tell me what it reads, it should be around 44mpg, less than 40mpg and its broke (thermostat, CTS, timing, lambda etc)

I have tryed this, mine started off at about 45 then gradually started going down and sitting under 40mpg. Ive changed lambda, and thermostat. Not done cts or timing. Cts is easy enough, would you be able to have a look at timing for me Fred@BTM

 

[Darius]

This is exactly my problem. Im seeing 27.8 normal driving. Just seems like its drinking fuel like its going out of fashion. Ive got a decat and the fuel smell is soo strong too. I think mines running really rich

I think it's the map you have on the car