Technical Abart won't start - Faulty Fuel Level Sensor?

[typecastboy]

Got my new key cut today so at least I can lock it, and start it . . . or can I?

Battery was flat, had it on charge for a few hours, still nothing so plugged in a booster which turns the engine over. Dash was showing that the inertia switch had activated in the crash so I have reset that successfully. Now it just turns over but doesn't start.

MES shows that the Fuel Level Sensor has a fault. Gauge shows zero so I'm going to get a can full and put it in just in case I'm actually completely out of petrol however there's obviously an issue with the sensor. Does the sensor have a fuse or is it likely to be the sensor? Where is the sensor anyway?

I'm dying to start this beast up for the first time!!

 

[typecastboy]

I'm assuming this is the sender unit, not a sensor as MES calls it?

I guess I'll have to get the Haynes out to see where it is. I'm wondering if it's under the plate under the rear seat but I'm probably wrong.

Would a faulty sender/sensor stop the fuel from flowing? Surely that's the inertia switch that does that?

 

[typecastboy]

I’ve done some further research and am partly answering my own question for future reference of anyone else that has this problem.

So, the sender is under the rear seat pad covered by a black bolt on circle of metal. You need to fashion a tool to get it out or possibly a screwdriver and a hammer to get it started.

Will have to get it out to make sure I get the part number right but there seems to be plenty on eBay.

Still don’t know whether this actually affects the flow of fuel or not.

 

[varesecrazy]

Does the tank pump run for @5 seconds with key at MAR? Should do..only cutting off when rail pressure is up.

The plastic ring.. tapping it around should work.

But can be TIGHT.. see GUIDE in mk1 punto section

 

[Ralf S.]

The sensor/sender won't stop the car starting. It only tells you how much fuel you have available, even if it thinks it's zero and it isn't.

If you can hear the fuel pump priming when you turn the ignition on, then that's good. If you can't, or you can but there's no fuel coming out at the fuel rail, then that's less good.

I think the immobilisor works by shutting the sparks and the fuel pump, so next question is "are you sure the key code is good"?


Ralf S.

 

[typecastboy]

The sensor/sender won't stop the car starting. It only tells you how much fuel you have available, even if it thinks it's zero and it isn't.



If you can hear the fuel pump priming when you turn the ignition on, then that's good. If you can't, or you can but there's no fuel coming out at the fuel rail, then that's less good.



I think the immobilisor works by shutting the sparks and the fuel pump, so next question is "are you sure the key code is good"?





Ralf S.

Thanks for that. I’m waiting for a new battery tomorrow and I’ve bought a can of petrol to put some in. I’m hoping it’s something simple like that or a relay/fuse. It’s always possible that the sender wasn’t working and the previous owner ran out of petrol at speed and the power steering going caused them to crash. Only a theory but a possible one. Very, very frustrating.

 

[typecastboy]

Sorted. I thought I would take the top off of the sender. The black metal bit.

Took the seat pad out and that black metal piece was undone. Just sitting there. Looked underneath and the electrical plug was disconnected and the white fuel pipe too. Put them back on and the engine started and the fuel level showed as a virtually full tank. The pipe popped off and petrol started pissing out.

I then found a little white retaining clip. Put that on. Restarted and it’s fine. Car now stinks of petrol. Tried to move it but with a knackered battery it stalled. Not before I gave it a few revs though!

Still work to do but over the moon.

Complete mystery why someone would have done that though. It’s clearly been done on purpose.

 

[chris3234]

Sorted. I thought I would take the top off of the sender. The black metal bit.

Took the seat pad out and that black metal piece was undone. Just sitting there. Looked underneath and the electrical plug was disconnected and the white fuel pipe too. Put them back on and the engine started and the fuel level showed as a virtually full tank. The pipe popped off and petrol started pissing out.

I then found a little white retaining clip. Put that on. Restarted and it’s fine. Car now stinks of petrol. Tried to move it but with a knackered battery it stalled. Not before I gave it a few revs though!

Still work to do but over the moon.

Complete mystery why someone would have done that though. It’s clearly been done on purpose.

View attachment 202895View attachment 202896View attachment 202897

Perhaps some sort of crude security measure to stop it being nicked?
Allthrough the pipe Alos disconnected seems to make it unlikely

 

[typecastboy]

Perhaps some sort of crude security measure to stop it being nicked?

Allthrough the pipe Alos disconnected seems to make it unlikely

Yeah really weird. A friend suggested maybe there was a leak. I’ll get it up in ramps as soon as the new battery comes but I think that’s unlikely. Really weird.

 

[Ralf S.]

I wonder if someone had started to remove the fuel pump for some reason..?

What kind of clip do the pipes have on them? They need some kind of clamp to stop them coming out (as you discovered, they're not just a push fit).

Usually there's a W shaped flat metal clamp that fits around the two fuel pipes and bolts to the pump between the pipes... but your picture seems to show there's no bolt hole on the pump, so this must have a different arrangement to hold the pipes firmly in place.



Ralf S.

 

[typecastboy]

I wonder if someone had started to remove the fuel pump for some reason..?



What kind of clip do the pipes have on them? They need some kind of clamp to stop them coming out (as you discovered, they're not just a push fit).



Usually there's a W shaped flat metal clamp that fits around the two fuel pipes and bolts to the pump between the pipes... but your picture seems to show there's no bolt hole on the pump, so this must have a different arrangement to hold the pipes firmly in place.







Ralf S.

I will look at some eBay pictures of replacement ones but it was just a small plastic clip that once inserted onto the plug end it stops it from pulling off. It was clearly the pressure of the flow of fuel that pushed it off before I saw the clip.

Just looked at eBay and the Haynes manual and there are no other clamps.