bad to drive on a low fuel warning light?

teednab-el

Is it bad to drive a 2001 diesel tdi on a low fuel warning light?

I will admit openly that I always do it. I always let it down to about 50 miles of fuel left. The warning light comes on when there is about 75miles of fuel left in the tank according to ECU display.

People say it f&cks up engine and fuel pump etc but does the fuel filter prevent that from happening? Can it f@ck up engine?

MidlandsM

no, it'll not fu(k up yer engine Op, drive her on untill she STALLS!

MugMugs

Getting those things going after running out is a pain in the bottom. That said, the worst that can happen is all the muck and junk in the.bottom of the tank is brought into the engine clogging the fuel filter etc...

teednab-el

MidlandsM wrote: »

drive her on untill she STALLS!

Il never do that.

Green Diesel

Could be a bit of gunk in the bottom of the tank, I wouldn't do it regularly.

teednab-el

MugMugs wrote: »

Getting those things going after running out is a pain in the bottom. That said, the worst that can happen is all the muck and junk in the.bottom of the tank is brought into the engine clogging the fuel filter etc...

Is 50miles of fuel in tank dangerously low?

Max Power1

I do it every week

Let her go 40-50 miles after the red light
The most ive gone before chickening out was 65 miles
(01 1.9 tdi golf)

shedweller

No, it won't wreck your engine. The fuel pump won't burn out because it is cooled by fuel. When the fuel runs out, the engine stops and there is then no need to cool the fuel pump anymore.
As for dredging up dirt from the tank, that won't happen either because the pump inlet is at the bottom of the tank, where the dirt supposedly lives. There's a strainer on it anyway, with holes sized so that anything that does get through won't seize the pump and will instead be caught by the fuel filter in the engine bay.

I checked my fuel pump once and it was clean. There was also a bowl type thing in the fuel tank that the pump stood in. This bowl looked about 5 or 6 litres in volume. It had two or three 8mm holes in its base so i can only assume that the bowl stays full all the time up till there is no more fuel in the rest of the tank. At which point it starts emptying as you drive.

creedp

Max Power1 wrote: »

I do it every week

Let her go 40-50 miles after the red light
The most ive gone before chickening out was 65 miles
(01 1.9 tdi golf)

Not clever but I got it down to 0 on the trip last week. Was rushing to get to creche and didn't have time to stop for fuel on way home .. trip said 45 miles left as I headed on a 40 mile journey ... started to get really worried when it jumped from 30 to 5 miles with 10 miles left:) Having said that I normally let the warning light come on before I fill up except when I'm heading off on a long journey and then I simply top up.

teednab-el

teednab-el wrote: »

Is it bad to drive a 2001 diesel tdi on a low fuel warning light?

I will admit openly that I always do it. I nearly let it down to 50 miles, warning light comes on at about 75miles of fuel left according to ECU display.

People say it f&cks up engine and fuel pump etc but does the fuel filter prevent that from happening? Can it f@ck up engine?

I would always have around 50miles of fuel left in the tank but top it up after that. But was told by someone that I shouldn't do that as dirt from the fuel at that level in the tank can ruin engine. I mentioned the fuel filter stopping the dirt but didn't get much of a hearing so no better place than ask motor boardies here for their opinions.

Matt Simis

On a petrol engines its fine, do it all the time and have stalled out of fuel twice (in my defense the fuel level guage was misreading on one of them). As noted the fuel pump is at the bottom of the tank, any dirt is already "on" or around that pump. The fuel pump has a screen in front of it (ie a filter) and after that, it runs through the actual fuel filter. So even if something got picked up, you have double filtration to cope with it.

Diesels can get locked or air in the system which requires bleeding etc.

djimi

My question would be why would you want to run your car in the red on a regular basis? I can understand getting caught short occasionally, but surely most people treat the top of the red as empty and top up from there?

Stinicker

djimi wrote: »

My question would be why would you want to run your car in the red on a regular basis? I can understand getting caught short occasionally, but surely most people treat the top of the red as empty and top up from there?

shhh, man theres a recession on goddammit.

teednab-el

djimi wrote: »

My question would be why would you want to run your car in the red on a regular basis? I can understand getting caught short occasionally, but surely most people treat the top of the red as empty and top up from there?

There is a function on my ecu that tells me how many miles the car can drive before running out of fuel. If I didn't have that then I would be topping the minute the light comes on.

seamus

djimi wrote: »

My question would be why would you want to run your car in the red on a regular basis? I can understand getting caught short occasionally, but surely most people treat the top of the red as empty and top up from there?

Since I always do a complete fill of the tank* and I budget for about one fill per month, I'll often run on a pretty low tank towards the end of the month. I've an electronic display so the car tells me how many miles I have left, but when it gets to about 50km remaining, it beeps and just says, "Fill up now" or something like that and won't tell me how far I have left to go. So I just watch the odo.

I'll usually wait until that happens unless I have a reason for filling up (long trip, etc).

On my previous car I would generally top up once I hit the red if I happened to be passing a garage, but on occasion waited for the red light to come on.


* I know it's not best practice, but I'm not that desperate to save cash to fill up by €20 four times a month

Stinicker

lolo, anyone else getting a google ad for barrels on red diesel in the lower corner? Very apt advertising I must say lol!

Max Power1

Stinicker wrote: »

shhh, man theres a recession on goddammit.

+1

at north of 75-80€ a fill, I try to space them out as much as possible!

Matt Simis

djimi wrote: »

My question would be why would you want to run your car in the red on a regular basis? I can understand getting caught short occasionally, but surely most people treat the top of the red as empty and top up from there?

Cos Im driving too fast to stop for fuel!

keithclancy

I never will, personally have the experience getting air out of the fuel line every single time i service the car since to get at the oil filter you have to disconnect the fuel line.

No primer either on the Volvo V50/S40 2.0D so you have to improvise something or get the original Volvo vacuum pump. ffs.

Thing the C5 has the same engine and it has a pump builtin .. WHY VOLVO WHY ??!?!



Saying that i've driven with 10km left on the range estimate because I refused to pay the extra 15cent a litre to fill up in Germany.

creedp

djimi wrote: »

My question would be why would you want to run your car in the red on a regular basis? I can understand getting caught short occasionally, but surely most people treat the top of the red as empty and top up from there?

I wouldnt consider it getting caught short to run the guage into the red. The 'red' on the guage or the warning light are there to remind you that you only have a certain amount of fuel left not that have to fill up immediately. Having said that I would rarely leave it much beyond the warning light coming on to fill up.

pred racer

Stinicker wrote: »

shhh, man theres a recession on goddammit.

Wheter you buy it today or tomorrow it still costs the same:rolleyes:

101sean

Real men know exactly how far they can drive with the needle wrapped round the stop and the light burning your eyeballs

There's usually 10 litre/ 2 gallons left when the light comes on in anything I've owned. I've only ever been caught out once when I parked on a hill intending to fill up in the morning. Wouldn't start and I had a long walk with a can!

Deliberately ran my 101 out of fuel last year as the tank had to come out, thought it would never stop! Even then I drained over a gallon out after it stopped, is a 24 gallon tank though.

Where To

I'm getting a nasty taste of diesel in my mouth just reading this thread :pac:

Always keep tank topped up as much as possible, you never know when you might need it.

teednab-el

Where To wrote: »

I'm getting a nasty taste of diesel in my mouth just reading this thread :pac:

Always keep tank topped up as much as possible, you never know when you might need it.

We all need diesel at some stage but that doesn't justify why you should keep it topped all the time unnecessary when you don't need to.

TPM

Just dont try it in a rover 75 with the bmw engine :eek:

MidlandsM

teednab-el wrote: »

Il never do that.

shure yer doing it as it is, you'll get caught yet.:p

Mycroft H

Fuel light roulette. I played it inadvertently once in a starlet cos I was quite lost in a part of the city I was not too familiar with. I let it get so bad that it cut out one side of a roundabout and started again on the other

Jesus Shaves

teednab-el wrote: »

We all need diesel at some stage but that doesn't justify why you should keep it topped all the time unnecessary when you don't need to.

But what if you had to drive to the length and breadth of the country in an emergency:eek:

Mycroft H

24hr petrol stations?

Where To

teednab-el wrote: »

We all need diesel at some stage but that doesn't justify why you should keep it topped all the time unnecessary when you don't need to.

I struggle to see the logic in this, and I know plenty of people that do this.

Why is it unnecessary? You are going to need fuel if you are going to be driving your car, and a lot of unforeseen events could happen between one full from empty and the next.

It's a car not a jumbo jet :pac:

teednab-el

darokane wrote: »

But what if you had to drive to the length and breadth of the country in an emergency:eek:

Car wont do length and breadth of the country on a full tank so you are fe*ked there anyway too.

creedp

Where To wrote: »

I struggle to see the logic in this, and I know plenty of people that do this.

Why is it unnecessary? You are going to need fuel if you are going to be driving your car, and a lot of unforeseen events could happen between one full from empty and the next.

It's a car not a jumbo jet :pac:

One reason .. I don't like filling stations so I try to visit as little as possible .. I fill up when I need to and then don't go back until I need to .. If I need to go on a journey I fill up in advance. Seems reasonable to me .. How the hell will we ever be able to switch over to EVs if we need a couple of hundred miles in the tank at any one time?

teednab-el

Where To wrote: »

I struggle to see the logic in this, and I know plenty of people that do this.

Why is it unnecessary? You are going to need fuel if you are going to be driving your car, and a lot of unforeseen events could happen between one full from empty and the next.

It's a car not a jumbo jet :pac:

Because fuel is expensive now and unless you are very well off, people are going to try and get value with what they put into their car.


You are also adding more costs on to your car when you continuously drive it with a full tank, i.e new tyres sooner, brake pads put under more pressure due to extra load, shocks due to extra weight and your car engine has to work that bit harder in getting acceleration up due to extra weight added. I never fill the tank up but go about half way.

pippip

teednab-el wrote: »

Because fuel is expensive now and unless you are very well off, people are going to try and get value with what they put into their car.


You are also adding more costs on to your car when you continuously drive it with a full tank, i.e new tyres sooner, brake pads put under more pressure due to extra load, shocks due to extra weight and your car engine has to work that bit harder in getting acceleration up due to extra weight added. I never fill the tank up but go about half way.

In fairness alot of that extra wear will happen regardless with more trips to the station.

teednab-el

pippip wrote: »

In fairness alot of that extra wear will happen regardless with more trips to the station.

Every ibs or kg added on though will have its effect for extra wear. The more thats added the sooner parts have to be replaced.

Mycroft H

Ahhh lads. To be honest the wear in both sides of the argument is going to be negligible

Mr Benevolent

I've played fuel light bingo a good few times, my closest has been 2L left in the tank.

creedp

teednab-el wrote: »

Because fuel is expensive now and unless you are very well off, people are going to try and get value with what they put into their car.


You are also adding more costs on to your car when you continuously drive it with a full tank, i.e new tyres sooner, brake pads put under more pressure due to extra load, shocks due to extra weight and your car engine has to work that bit harder in getting acceleration up due to extra weight added. I never fill the tank up but go about half way.

I don't frequent stns that take the complete p1ss with the price per litre. The local petrol stns are not the cheapest so I would consider frequent runs to further away stations to be a waste of time and fuel. I wouldn't consider the extra fuel saved by 1/2 fills would compensate for this. In relation to the extra weight I think it would have a negligible effect. I'd save more by leaving the OH at home more often:). I agree though that better value is needed from fuel now so I don't drive like the house is on fire anymore (except for a decent burn every know and gain to get rid of the cobweds in the exhaust), I empty the clutter out of the car, keep it serviced and check the tyre pressure regularly. After that its a case of grin and bear it or walk.

Melted

TPM wrote: »

Just dont try it in a rover 75 with the bmw engine :eek:

out of interest, why?

pippip

There is an ad that runs on Newstalk advising against letting you car go low on fuel as it strains the fuel pump. Nothing about dirt getting into the system.

Not sure who runs it or if its endorsed by the RSA.

TPM

TPM wrote: »

Just dont try it in a rover 75 with the bmw engine :eek:

Melted wrote: »

out of interest, why?

Increased wear on the in tank fuel pump apparently which will then fail. If the in tank pump has failed keeping the tank over one third ish full will keep you motoring.

Jesus Shaves

pippip wrote: »

There is an ad that runs on Newstalk advising against letting you car go low on fuel as it strains the fuel pump. Nothing about dirt getting into the system.

Not sure who runs it or if its endorsed by the RSA.

topaz, texaco, shell?

pippip

pippip wrote: »

There is an ad that runs on Newstalk advising against letting you car go low on fuel as it strains the fuel pump. Nothing about dirt getting into the system.

Not sure who runs it or if its endorsed by the RSA.

darokane wrote: »

topaz, texaco, shell?

Do you reckon the like of them would somehow benefit from running such an add?

pippip

darokane wrote: »

topaz, texaco, shell?

You'd think

No they have a few different ads, mostly about how to save fuel and safer driving.

maggy_thatcher

teednab-el wrote: »

You are also adding more costs on to your car when you continuously drive it with a full tank, i.e new tyres sooner, brake pads put under more pressure due to extra load, shocks due to extra weight and your car engine has to work that bit harder in getting acceleration up due to extra weight added. I never fill the tank up but go about half way.

A full tank (50l) of petrol weighs about 35kg - about the weight of a child. It's really not going to make a whole lot of difference when you consider the rest of the vehicle (excluding passengers) is 1000kg+.

Jesus Shaves

RoverJames wrote: »

Do you reckon the like of them would somehow benefit from running such an add?

i was joking;)

teednab-el

maggy_thatcher wrote: »

teednab-el wrote: »

You are also adding more costs on to your car when you continuously drive it with a full tank, i.e new tyres sooner, brake pads put under more pressure due to extra load, shocks due to extra weight and your car engine has to work that bit harder in getting acceleration up due to extra weight added. I never fill the tank up but go about half way.

A full tank (50l) of petrol weighs about 35kg - about the weight of a child. It's really not going to make a whole lot of difference when you consider the rest of the vehicle (excluding passengers) is 1000kg+.

Every kg makes a difference. Why do f1 cars and rally cars try to be as light as possible, for acceleration so the more weight you add the more fuel you will use.

shedweller

teednab-el wrote: »

Every kg makes a difference. Why do f1 cars and rally cars try to be as light as possible, for acceleration so the more weight you add the more fuel you will use.

Thing is, i once tried a full blown weight reduction on my car to see if it would improve mpg much. All i left in the car was the spare wheel, jack and wheel brace. I even removed the rear seat for the full tank. At least 20kg by my weight-ometer!
It felt more....sporty (i know, i know!).....and i thought i would see an improvement. But a month later, when i refilled, there was no improvement at all.
So, unless you have a boot full of tools and junk that weighs as much as a person you won't see an improvement by clearing your car out.
It'll be a cleaner car though!

maggy_thatcher

teednab-el wrote: »

Every kg makes a difference. Why do f1 cars and rally cars try to be as light as possible, for acceleration so the more weight you add the more fuel you will use.

The differences you would have would be so minimal in any kind of "regular" car, that it would probably be offset by the more frequent stops you make to fill up with fuel!

Let's not forget the obligatory xkcd:

seamus

teednab-el wrote: »

Every kg makes a difference. Why do f1 cars and rally cars try to be as light as possible, for acceleration so the more weight you add the more fuel you will use.

Scale is important though.

An F1 car weighs 640kg. Reducing the weight of the car by 3kg, will give you roughly a half percent increase in performance. When races are decided by fractions of a second, that half percent is huge.

A Passat by comparison weighs 1,400kg. Reducing your carrying weight by 14kg will give you roughly a 1% improvement. The only difference is that your life is not decided by fractions of a second, so you will notice no major difference overall. Theoretically it means that for every 100,000km, you have "saved" 1,000km of wear. And that's at best, it would probably be far less.
This is functionally meaningless for most people since if the life of a part is rated at 100,000km, then it will already be "due" replacement at 99,000km, and you may at best get to delay the replacement by a couple of months.

This could be a world of difference if you cover 200,000km per year, but for most of us who would barely cover 100,000km in the life of a single car, the benefit is meaningless.

shedweller

maggy_thatcher wrote: »

The differences you would have would be so minimal in any kind of "regular" car, that it would probably be offset by the more frequent stops you make to fill up with fuel!

Let's not forget the obligatory xkcd:

Thing is, thats fine if you have a business and time spent saving fuel or saving on fillups could be time spent making money. But what if you are a PAYE worker? I get paid a salary and don't get paid extra by coming in early or staying late. So once i'm outside work, i'm not earning any money.
Do you see what i mean?