Erratic Fuel Guage

[jekel 10]

Hello, fuel gauge has started has started playing up, reading low all time now I'd say, think there's bout half a tank at least in there, nearly reading empty.

Started when accelerating shoots right down, will always a bit, but not that much.

 

Last night gave it a spirited boot of acceleration exiting a petrol st5ation onto motorway jerked it back into life read 3/4 full for bout half an hour then reverted to empty.

 

Common probs.? Sender, gauge, relay connections?

 

Had look at fuel pump before looked very new, nearly everything is on car so chances is.

 

Where's the earth connection for sender, symptons could be of a dodgy earth

 

It's a VR6, 94

 

Cheers

[Philly-R6 0]

The circuit is very simple: there is a sender (with the pump in the tank), and the fuel gauge.

 

As you say, it is either the gauge or the sender.

Bentley publishers have a page on testing gauges and senders:

http://www.bentleypublishers.com/tech/vw/bentley.vw1301.testing.htm

Empty values are 288 Ohms and full values are 37 Ohms.

 

You could un-plug the connector from the fuel pump (through that round black panel in the boot) and put some resistors across the sender (pins 2 & 3).

Does the fuel gauge react as you expect?

 

If it does, look at the values reported by the sender...

[oxfordpaul 0]

I had this once and the problem was that the pump had come adrift from its fixing so was literally floating around the fuel tank causing the gauge to go up and down. That would be my first check to make sure it's located in it's fixing correctly, kind of screws into the tank floor from memory.

[jekel 10]

I had this once and the problem was that the pump had come adrift from its fixing so was literally floating around the fuel tank causing the gauge to go up and down. That would be my first check to make sure it's located in it's fixing correctly, kind of screws into the tank floor from memory.

 

I had a look at the pump yesterday, before seeing your message, and that's exactly what had happened mate, reattached it, it's like one of those position and twist 30 degree things.

It would explain why it's feeling hesitant after leaving work, turning right at two big roundabouts then putting foot down on motorway slip road, felt like fuel starvation.

 

Has'nt fixed gauge which expected it to, but think sender is now OK, it's reading 127 ohms and looks bout 1/3 to half full which sounds bout right from info above. Probs. the actual gauge, but pump certainly wanted re-attaching, and hopefully will pull down sliproad tonight in more spirited fashion