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Discussion Starter · #1 ·
I noticed that my car have some problem when fuel is low. But no reserve. I'm driving 100km/h and in a moment I feel like I put off the foot from pedal. Of ocurse I'm still holding my foot on the pedal. After few second acceleration comes back. Second situation from yesterday. 5th gear and full throttle and again same situation. I still holded 100% gas pedal and after few seconds I felt a tug and acceleration comed back. Does this mean my fuel pump is going to die or maybe fuel tank level is faking?
It is very dangerous while overtaking. 1.6 AUS engine.
What's more strange I don't have any errors in ECU.
 

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If you want to throw parts at it, then you could just drop in a new complete sender unit, and that'd cover both those options.

If it were my car, I'd brim the tank and see how many miles I was getting, and compare it to how many miles you usually get out of a tank. If you need a reference, my 1.6 does anywhere from 430-500 miles (692-804 km) on a tank, depending on how economically I drive.

Alternatively, when it starts acting up, brim the tank and see how many litres it takes to fill it. If it's around 55 litres, then you know you were actually almost out of fuel and the level sensor is inaccurate. Tank is 55 litres, but the car usually takes slightly more.

A dying fuel pump will perform better in a full tank of fuel, because the fuel around it helps to keep it cool. As you get low on fuel, it gets warmer and sticks.
 

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Discussion Starter · #3 ·
I usually did 415-450km on one tank in only city. But now I'm more driving outside city and now I have 540km and still no reserve. I will check how many liters car will fit. Maybe something wrong is with fuel level sensor. If not I will replace whole unit.
 

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Discussion Starter · #4 ·
How many liters in the tank = reserve light on?
I usually tank 50/51 liters from reserve to full. So if the fuel tank is 55 then 4 liters are left in my car.
 

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Discussion Starter · #6 ·
So fuel level sensor is ok. We'll see how car act now. If it starts again loosing power at low fuel then I have to replace fuel pump. I will post restult in a month.
 

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They do not, no.

If your car stops starting and you want to test if it's the pump, have someone gently hit the fuel pump access lid with a blunt instrument, while someone else cranks the car over. The hitting should temporarily bring a dead pump back to life.
 

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I noticed that my car have some problem when fuel is low. But no reserve. I'm driving 100km/h and in a moment I feel like I put off the foot from pedal. Of ocurse I'm still holding my foot on the pedal. After few second acceleration comes back. Second situation from yesterday. 5th gear and full throttle and again same situation. I still holded 100% gas pedal and after few seconds I felt a tug and acceleration comed back. Does this mean my fuel pump is going to die or maybe fuel tank level is faking?
It is very dangerous while overtaking. 1.6 AUS engine.
What's more strange I don't have any errors in ECU.
Hope fully this will help as my golf (tdi 130 ) had same problem, fuel pump roughly the same so may be your problem..

Take pump out, at bottom of pump there is a flap, controlled by a float, flap opens when enough fuel in tank, flap covers a small pipe leading to bottom of pump, i found a "lump" of debris in small pipe, which stopped fuel getting to pump, if tank is/was over 1/4 full, fuel could get to pump over bottom part of pump (there's an outer covering )without going through pipe.....i did have photos of pipe/debris but on old phone so now gone sorry, debris in pipe was not easy to see because pipe not see through but may be worth checking,
My symptoms were same as yours, no throttle at speed, and in traffic, car would stop until enough fuel got past slight blockage, but only when on 1/4 tank or less, with a half/full tank there was no problem.
Good luck
Blackdogtaff
 

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Discussion Starter · #11 ·
For now I'm driving with full tank and don't have any problems. So 99% it is fuel pumps. Thanks for the clues i will check this. Or just never down below 1/2 tank.
 

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Discussion Starter · #14 ·
I bought VDO/Continental pump. Will see how it will act with low fuel and let you know.
 
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