Technical Fuel leak from rear arch, from this black box.

[xf1ref]

If you want I can look up the wiring diagram and you can confirm it's operation, but as you can hear it opening I suspect it would just be a waste of your time

I definitely hear the valve opening when revving the engine. I also removed the connector to check if indeed the sound stops. I can test with a multimeter if there is a voltage even if is modulated.
I remeber now that I bought two new solenoid valves and both are working like the original one.

 

[The Panda Nut]

I think it was Murphy74 who has issues and eventually sold his car (Panda City Cross) as the useless dealers couldnt fix it. I have had two failures of the evapouration solenoid and cannister. The whole job done by the dealer including evap cannister and solenoid and breahter hoses and a map sensor (£128) cost £725 three years ago. Evap canister was £47.25 +vat from the main dealer. S4P would no doubt be cheaper. Fortunately most of this was covered by warranty.

 

[The Panda Nut]

Well that will be you problem, it's not closing fully

It should remain closed with the engine cold

It should remain closed at idle

I suspect the ECU is doing its job properly as you can hear the solenoid opening as you rev the engine

Whether is a fail on fit part, or damaged due to petrol still in the canister I can't say

Here's Fiat take

​

MANAGEMENT OF FUEL VAPOUR RECIRCULATION​

The strategy controls the position of the vapour cut out solenoid valve as follows:

• during starting the solenoid valve remains closed preventing the fuel vapours from enriching the mixture excessively; this condition persists until the engine coolant reaches 65° C;
• when the engine has warmed up the electronic control unit sends the solenoid valve a square wave signal (duty-cycle) and the opening is modulated.

In this way the control unit controls the quantity of fuel vapours sent to the intake, preventing considerable variations in the mixture strength.

In order to improve engine operation, the solenoid valve operation is inhibited, maintaining the same closure position in the operating conditions listed below:

• throttle valve is closed position
• speed below 1500 rpm
• intake manifold pressure below a limit calculated by the control unit depending on the rpm.

If you want I can look up the wiring diagram and you can confirm it's operation, but as you can hear it opening I suspect it would just be a waste of your time

MES will test too. You can ... just hear it tick.

 

[koalar]

I definitely hear the valve opening when revving the engine. I also removed the connector to check if indeed the sound stops. I can test with a multimeter if there is a voltage even if is modulated.
I remeber now that I bought two new solenoid valves and both are working like the original one.

Yellow and red cable on this car is the switched ground side

The other cable is perment battery voltage


Here's mine blue pipe removed no vaccum at idle

And vacuum if I remove the electrical connector as well

 

[xf1ref]

Thanks for diagrams and all advice. I will check if there is any voltage on the connector at idle.

 

[xf1ref]

Definitely there is voltage on idle but the vacuum doesn't change if i plug the connector. Based on the management it should remain closed at idle.

 

[koalar]

When the electromagnet (1) is energized it attracts the shutter (2) that overcomes the load of spring pack (3) to close the port (4) and prevent fuel vapours from passing through.​

It works the oppersite way to most

I assume all the petrol pandas are the same as my eco 2010, is the only info given on elearn

You could just disconnect the connector

Add battery power and ground and suck on the pipe

It's very unlikely to be a an electrical fault, being ground switched any open or shorts should be detected and throw the appropriate code any how you can hear the solenoid click

Opening and closing the solenoid via software is easier if you have access to the equipment as per @The Panda Nut if you hear the solenoid and it still will not hold a vacuum, it's mechanically not closing.

We need to be 100% as they aren't cheap here in the UK

From memory once the conditions are meet for it to operate it opens and closes around 5 times a minute

My best guess is the charcoal is breaking down, entering the valve and mechanically stopping it from closing properly

 

[jrkitching]

My best guess is the charcoal is breaking down, entering the valve and mechanically stopping it from closing properly

That's certainly one possibility. And the alcohol content in currently available fuels may be increasing the rate of breakdown. We've seen more of these failures since the widespread use of E10 fuel - coincidence, or not?

Another is that liquid petrol has entered it and evaporated, leaving a sticky residue which is gumming up the valve.

Whatever, not putting more fuel into the tank than the handbook advises would seem a sensible precaution.

Sadly this prevents accurately measuring actual consumption between two consecutive fillups, but that's a small price to pay for not having an evap system failure. But if you fill to the cutoff each time and measure it over ten fillups, you'll get pretty close to the correct actual figure. And measured over a hundred, it'll be within a fraction of a percent of the actual figure.