faulty fuel warning sensor

Hi guys, I’m enjoying my Cali Vintage very much but have an irritating issue with the fuel warning sensor that I would like to sort out. I asked my local dealer (Newcomb Bros, Essex) if they would check it out for me when doing a service last year, but they were unable to fix it. But the bulb now mostly shows when I turn the ignition on and goes out when the engine starts, but never comes on when I’m getting low on fuel (I did at one point run out of fuel with no light coming on). My question is; where can I buy a sensor from and will it be fairly straightforward to fit? I have had a quick look to see if I can purchase a sensor but haven’t been able to find anywhere that sells them separately to the complete fuel pump unit and there would certainly be no point in spending that much just to avoid paying more attention to how many miles I have done since the previous fill up! Any help greatly appreciated.

Not sure if this would be the same?

Alternatively if you can find the part number, try googling Guzzi followed by the number, it often comes up with a supplier.

Thanks’ Don I’ll check it out.

Unfortunately Don the fuel sensor that is displayed in the link you gave is not the correct type, mine is part of the fuel pump assembly, which is all inside the tank. I haven’t as yet been able to find a way to get a part number (other than I guess going in and asking a 'Guzzi dealer). I’m also wondering if trying to replace this part separately will mean a loss of the electrical insulation integrity. Maybe I’m just going to have to “dive in” and have a look! Any other thoughts/suggestions will be gratefully received. :slight_smile:

Yes I think it’ll have to be a case of get it out and “give it a good coating of looking at”


Here’s a link to the parts book. Page 37 suggests it’s all part of the fuel pump assembly.
May be worth a call to Gutsibits to see what they can offer.


No gauge or anything on my old bikes, so I’ve got those stitch counters that slip onto knitting needles threaded onto cables. Set it to the mileage when I fill up and I can keep track easily.

Fuel sensors are a bit of a weak spot.
On Cali EVs and a few other models it’s possible to swap to a traditional tap with a reserve. Passes plenty enough fuel to support FI.
Just a thought

thanks all for your replies and suggestions. I’ll let you know how I get on.

Parts book link is really helpful Don, but as you say the way they show it, it’s all one component, very expensive! So a call to Gutsibits might well be in order. Thank’s.

I do reset the trip meter, but my problem is, if something is fitted on my bike I like it to work! :slight_smile:

And yet you still own Guzzi’s?

:laughing: I’m just a foolish dreamer.

Newcombe Bros still do servicing but are no longer Guzzi dealers. The nearest to you are Colchester Kawasaki who now sell and service Guzzis (but only up to 6 years old, or was it 10 years?)

Fuel gauge on the Stelvio is a bit random, shows full when full for about 10 miles then half full until it goes onto reserve (or last 30 miles as there is no reserve)

Best of luck

[quote="Drew BAnd yet you still own Guzzi’s?[/quote]

:laughing: I’m just a foolish dreamer.[/quote]
Aren’t we all.

Petrol doesn’t conduct electricity. so all the movies with brake light wiring in the fuel tank…kaboom, is codswallop.

Having a browse around on this ere internet, I came across a reed switch sold by Pyro Dan in the states that may be the answer to your troubles and woes. The description reeds as follows:-
This is the tiny reed switch found in the sensor unit for the Sigma BC series bicycle computers, popular with many motorcycle riders. It can also be used to replace the reed switch found in the fuel level sensor in late model Guzzis. This switch is normally open but closes when subjected to a magnetic field. It is rated at 0.5 amps (6 watts at 12 vdc).
Might be worth an enquiry .

Yep, slightly off-topic but the Myth Busters guys tried to prove whether you can set yourself on fire if your mobile rings while you’re filling your tank at the pump - proved to be incredibly difficult, in the end they had to make a sealed perspex box, put EXACTLY the correct stoichiometric ratio into it, and set if off with a spark from an ignition coil.

Hi Don, only just noticed your post, looks really interesting, have no clue about how I would use it but will investigate further by sending an e-mail. If it works it’s a good cheap solution! Thanks very much

That requires a float having the magnet in it. As far as we know yours is the thermistor type(?), no moving parts, just it being immersed in the petrol or not changes its temperature and hence its resistance.