Fuel gauge crisis!!

apsbaketcase · Post by **apsbaketcase** » 18 Mar 2004, 04:30

My 405 1994 1.9 diesel, saloon, has an irratic fuel gauge. 1 minute it's 1/2 full then 3/4 then 1/4 full!!
Does anybody know what are the expected resistances are from the fuel gauges sensor, I can roughly judge the expected position from filling the tank from the yellow 'fuel low' warning light. Or is there another check possible??
Is there a check possible on the indicator gauge in the instrument panel.
THX
Ash
[8]

Peter D · Post by **Peter D** » 18 Mar 2004, 17:53

Put a meter across the tank sensor to ground and go for a run and see if the voltage is bouncing around. If so it would imply the sender unit is at fault. Regards Peter

VisaGTi16v · Post by **VisaGTi16v** » 18 Mar 2004, 20:14

my old visa had a great fuel gauge, it stopped going down just before the minimum so the light never came on and it never went into the empty bit. Of course I didnt know this until one day miles from home when the car suddendly conked out with apparently 1/8 tank left in it

DLM · Post by **DLM** » 22 Mar 2004, 21:38

If it's like the Citroen BX with the same engine (which I strongly suspect it is) then these senders do wear with age and get pretty unreliable. I'm relying on my yellow warning light nowadays as the only reliable indication of what's in (or not in) the tank.
As a first non-invasive check I'd give the contacts at the sender a good cleanup (underneath the back seat), before proceeding any further. If anything wet has ever got underneath the seat it doesn't do these contacts any good...