Seat Ibia 6K2 99-02 - Błąd 17834 - EVAP Purge Valve (N80): Open Circuit

Hello forum members

I wanted to ask people who know the subject for help.
In Seat Ibiza 6K2 FL from 2002 with 1.4 16v (AUA) engine error 17834 - EVAP Purge Valve (N80): Open Circuit.
After deleting the error pops up again after a few seconds.
I have already checked;
1. Electro-valve (N80) - normally closed and tight, opens after applying voltage from 7v. The resistance on the solenoid valve coil is about 26 Ohm.
2. Check the fuel filler cap - I do not see any irregularities
3. tightness and patency of the hose between the carbon filter and the fuel tank and between the solenoid valve and the throttle
4. The switch and fuse for the fuel pump circuit (the n80 valve is also supplied from it)
5.power supply - constant valve plus is approx
6.ground wire between the n80 valve and the ECU - no blockage.

I did some additional tests:
After disconnecting the plug from the n80 valve, the error repeats in the same way as with the connected valve.
The multimeter shows 8v on the disconnected plug
After connecting the valve, the voltage drops to zero. As if the computer that controls the mass cut off this mass.

In an act of desperation, I also replaced the entire activated carbon filter with a valve from another car, the same effect.

The only thing that comes to mind in this situation is: Damaged ECU.
Or incorrect readings from other sensors, on the basis of which the computer thinks that the tank ventilation system is out of order.
Unfortunately, I do not know on the basis of which parameters the computer diagnoses the efficiency of this system.
I am asking everyone for any more hints and suggestions.

I will add that apart from this error, there are no other errors and the car works without any problems.

best regards
Piotr

The problem is the open circuit of the N80 valve and nothing more, no hoses or plugs.
If the voltage drops to zero, it means that one of the wires is broken.
Check the voltage on the plug to ground and between the wire that gives ground from the valve ECU and the plus on the battery with the valve connected.
This way you will find which wire is damaged.
Measuring the passage with a meter does not make sense because it will show that it is ok and during the load there is such a large voltage drop that the valve plug is 0V.
You can connect a 5W bulb between the plus on the plug and the minus of the battery - it should glow all the time. When you connect the mass from the ECU to the bulb and to the plus on the battery, it should flash from time to time.

pmalik wrote:

6.ground wire between the n80 valve and the ECU - no blockage

Specify what's going on.
A typical electrical fault, a mechanical fault in this valve causes an error with the description "incorrect flow detected". Do you have ECU in the pit? Connectors not corroded? To check the cable, run a few A through it.

Hi

Thanks for fast reaction.
I checked the cables, but after your entries I can see that I could have made a mistake.
I checked the plus cable, i.e.
I connected a 5w bulb to the wire with a plus at the n80 valve and to the mass of the battery. The light bulb is on constantly.
However, I measured the cable between the ground at the valve and pin 64 in the ECU plug with an ohmmeter.
The measurement showed me not all of 1 Ohm. I decided that approx. 1 Ohm is the correct value for a wire in a bundle.
But in fact the measurement was taken without load. And there might be a dog buried here.
Today I will try to pass a pair of Amperes through the cable between the ground of the solenoid valve and the ECU plug and see if there is any problem here.

best regards
Piotr

Added after 1 [hours] 40 [minutes]:

Hi

I did another test.
Unfortunately, everything indicates that the wires are fine.
I gave the voltage to supply the carbon filter purge solenoid valve (N80) and I gave the mass on pin 64 of the ECU plug through the 5w bulb.
The valve was ticking when the circuit was closed and the light was on.
The pins on the ECU are clean.
The power supply to the N80 solenoid valve while the engine is running is also stable, the power supply has been checked with a light bulb and a multimeter.
The question is whether in this situation the source of the problem should be looked for in the ECU itself?
Is there anything else I can check before I go to the extreme?

Regards and I am asking for further help
Piotr