Fuel Gauge Problem

[Austria29]

Hi All

I'm experiencing some fuel gauge issues with my 1997 C5. Most of the time it works fine, but on longer journeys (above an hour) the gauge often drops to empty and gives a low fuel warning...

I've read about some similar issues in the USA, with most people claiming a fuel/injection cleaner will help things. Has anyone experienced similar issues over hear? As i understand it, our petrol (gas) quality is much better, so wasn't sure whether it is still likely to be the culprit

 

[mglapworth]

Hi All

I'm experiencing some fuel gauge issues with my 1997 C5. Most of the time it works fine, but on longer journeys (above an hour) the gauge often drops to empty and gives a low fuel warning...

I've read about some similar issues in the USA, with most people claiming a fuel/injection cleaner will help things. Has anyone experienced similar issues over hear? As i understand it, our petrol (gas) quality is much better, so wasn't sure whether it is still likely to be the culprit

Hi Austria 29
I’ve had the same problem with my 97 coupe - After I changed from 97 octane to 99 octane - shell vpower it now only happens occassionaly
On a long run the fuel gage will fall to empty for a while and then after a while will come back and work again - It may be a good idea to use injector cleaner - Does you engine check light come on at high revs and then go out at low cruising speeds ? It may be caused by dirt particles blocking the injectors at high fuel flow and then unblocking at low revs - maybe? Not 100% sure of above but will be trying with mine

 

[oelarse]

First , it is a good idea to read DTC codes on car .

Yes, It may cure your problem to use Techron . When your gauge show is 1/4 , fill the Techron in your tanks ( left).
Fill your car 100% with gas and the Techron will be mixed with fuel in both tanks .
You may have to repeat this several times and you may be solve the problem with your fuel sender or maybe not.

 

[mglapworth]

Thanks for info - ill give it a go!

 

[Austria29]

Hi Austria 29
I’ve had the same problem with my 97 coupe - After I changed from 97 octane to 99 octane - shell vpower it now only happens occassionaly
On a long run the fuel gage will fall to empty for a while and then after a while will come back and work again - It may be a good idea to use injector cleaner - Does you engine check light come on at high revs and then go out at low cruising speeds ? It may be caused by dirt particles blocking the injectors at high fuel flow and then unblocking at low revs - maybe? Not 100% sure of above but will be trying with mine

Thanks for the reply
I’ve not noticed the check engine light coming on at high revs, but I will try some injection cleaner anyway, along with some shell v power
Cheers

 

[Austria29]

First , it is a good idea to read DTC codes on car .

Yes, It may cure your problem to use Techron . When your gauge show is 1/4 , fill the Techron in your tanks ( left).
Fill your car 100% with gas and the Techron will be mixed with fuel in both tanks .
You may have to repeat this several times and you may be solve the problem with your fuel sender or maybe not.


View attachment 6586

Thanks, seems to work for a lot of people so will give it a try

 

[petchy56]

HI had the same problem with my 2001 couple of years back. Was advised by the Dutch CC to use BG44k. Two cans to make sure ,not cheap but did the job no problems since.

 

[robbiew]

I use seafoam

 

[benbay001]

First , it is a good idea to read DTC codes on car .

Yes, It may cure your problem to use Techron . When your gauge show is 1/4 , fill the Techron in your tanks ( left).
Fill your car 100% with gas and the Techron will be mixed with fuel in both tanks .
You may have to repeat this several times and you may be solve the problem with your fuel sender or maybe not.

Ive got the same problem as OP.

Ive been using fuel additive to try to sort it.

Wasnt aware of there being 2 tanks. Could you explain how they fill a bit better? (One fills first and then the next?)

 

[oelarse]

This is how later style fuel tanks looks like (medio 03-04) where fuelsenders are topmounted .
Ealier style 97-primo 03 have side mounted fuelsenders and are easier to service because you can remove a sender sideways without dropping any fueltanks.
On later style you need to drop both tanks when you service a fuelsender/fuelpump

 

[benbay001]

Thank you.

Mines an 02.

Ive been refilling after roughly 25-30 liters have been used (as i cant see the fuel level) will it be the case that im only emptying one side?

 

[oelarse]

Left tank with electric fuelpump give you 0-50% on your Gauge and your right tank with siphron pump give 50-100% on your gauge

 

[benbay001]

Thank you.
I thought I had imagined that the gauge began working below half a tank when I first bought it but now realise that may have been true!

Ill try to run the fuel down below half a tank and see what happens!

 

[oelarse]

A part of the pressurized fuel from the electrical pump in the left tank is feeded to the "siphon jet pump" in the right tank and used to empty this tank.
When the right tank is empty your left tank fuel level will start to decrease .
If your siphon pump stop working due a clogged orifice or something else you can end up stranded somewhere with a lot of fuel in the right tank and empty left tank IF you ignore
DTC that will appear when the PCM see no decrease in fuel level in right tank while the left tank decreases .

 

[Robert Craske]

I seem to remember it being high sulphur in the fuel in the US which we shouldnt have here anymore. When in the US you changed to a different brand it would solve the problem. Maybe be try Redex in the tank.

 

[97BlackC5]

First , it is a good idea to read DTC codes on car .

Yes, It may cure your problem to use Techron . When your gauge show is 1/4 , fill the Techron in your tanks ( left).
Fill your car 100% with gas and the Techron will be mixed with fuel in both tanks .
You may have to repeat this several times and you may be solve the problem with your fuel sender or maybe not.


View attachment 6586

+1 for Techron, I have a 97 C5 & have had the fuel gauge issue in the past. I bought about 3 bottles of Techron & did as stated. I now only use the best fuel at the pumps, but fuel gauge has been fine since.

 

[benbay001]

BG44k. Two cans to make sure ,not cheap but did the job no problems since.

Just bought two of these.
How did you do it?
Thanks

 

[Yellowshark]

I have owned my MY2001 from new doing 159,000 miles so far and have subscribed to several US forums since before 2001. Certainly back then this one was all over the airwaves. It was considered to be a design intent by some comedian in the design office. I have never seen anyone come up with a statement saying it is this because… Yes fuel is a common belief and my personal view based on my experience over the years is that it is poor quality fuel as these days I nearly always fill up at my local Shell station and rarely (compared with past) suffer the problem when I used to fill up all over the place.

There are many different descriptions on what happened, i.e. what fixed if for them, how frequently it occurred, intervals between occurrences etc. I found that running the tank down to a ¼ maybe less and then putting in a full tank normally cleared it fairly quickly. I have never used any sort of fuel additive ) not that I am suggesting that is a bad idea, Indeed I have recently been thinking about using the Redline product to give my fuel system a thorough clean out after all these years.

 

[benbay001]

I used the BG44K today.
Stopped at pump, emptied a can of it into tank using a funnel and filled to brim from 1/8th full.
Ill report back whether it helps!

Hoping when its clear, a bit more use will help keep it away. Car has only done 39k miles.

 

[Yellowshark]

Well we all know that opening your gob can lead to bad things happening. After fixing my engine backfiring problem I decide to go for a decent drive today. So went to my normal local Shell station, put in a bottle of fuel system cleaner (1st time ever), filled my 1/4 full tank to the brim with Shell's expensive higher octane petrol (only 3rd time ever) and set off with a smile on my face. 40 miles later the no fuel message appeared (1st time for a number of years). Particularly irritating as I was measuring my fuel consumption, so I booted her up to 100 briefly then relaxed again. The old adage if it aint broke don't fix it applies.