flickering petrol gauge..

[craigieeb]

Does anyone know why my petrol gauge is doing this........



could it be the level sender/sensor on the pump needing replacing?

(m20 "in tank" pump)

[spinner100]

might be the batterys in your si board.

[Brianmoooore]

SI board batteries don't normally affect the fuel gauge.
Interesting that the low fuel light is on! How much fuel actually in the tank?

[craigieeb]

there's about £15 worth ish...
it's seems to do it whether there is a load of petrol in there or not....

[Brianmoooore]

The light being on suggests that the RH level sender has somehow jammed with the float at the bottom, and the 'reading' is coming from the LH sender only.
Pull the three pin connector off at the fuel pump assembly, and use a piece of wire to short the brown wire in it to the other terminals in it.
One will make the light come on, and the other will (hopefully) produce a stable, although incorrect, level on the gauge.

[craigieeb]

ok i'll get on it in the morning and report back. cheers brian

[craigieeb]

Just "jumped" the connections there, and....

Solid brown, to brown/white stripe, light comes on,

Solid brown to brown/green stripe, nothing....

[Brianmoooore]

Take off the LH inspection cover, pull the connector off of that level sender, and short the two pins in the plug together as well.

[craigieeb]

man it's a bit cold out there,
anywhoo

looped the 2 connections on the left and nothing happened

[Brianmoooore]

Are you saying that with both sender plugs shorted out, and the ignition on, the fuel gauge doesn't move?

[craigieeb]

Sorry, i just looped the one on the left side....
just been back out to loop the Left connection,
and the Brown to Brown/green stripe on the Right,
and the gauge was reading a "full" tank

[Brianmoooore]

Leave the loop on the LH one and reconnect the RH one.
Does this give stable readings on the gauge?

[craigieeb]

L/H looped
R/H plugged back in
gauge reading half a tank

[hazd31]

im gunna jump on this one as i have the same problem, started happening recently guage is more than useless but the fuel light comes on fine when the fuel is low!

[danbear]

i also have the same problem lol

[psychochild187]

i had this
i banged on the dash and it stopped .
i bet its si board

[Brianmoooore]

L/H looped
R/H plugged back in
gauge reading half a tank

Looks like the LH sender is the problem then! Doesn't explain the fuel lamp on though.
IIRC, there's a possibility of repair to the sender - starting with a nut on the bottom.

[craigieeb]

i had this
i banged on the dash and it stopped .

that was my first attempt of fixing it, ye olde neanderthal style.... works sometimes lol

Looks like the LH sender is the problem then! Doesn't explain the fuel lamp on though.
IIRC, there's a possibility of repair to the sender - starting with a nut on the bottom.

i have a spare one in my spare fuel tank i'll change it and let you know if that was the problem..
as for the light being on, i'll pull out the sender and see why it's jammed strange that they both happened at the same time tho.

[psychochild187]

well i hit it often beacuse the temp gauge did it and then the fuel gauge
it works on the dash bulbs too
shame it doesnt work the mileage

[Chris-W]

Have you tried tightening the nut on the back of the gauge yet?

[craigieeb]

Well gotta had it to you brian,
you were spot on there,
just changed it over and voilà,
the gauge is reading just under a quarter of a tank with no flickering whatsoever

so thank you vv much mate