Threw a P0456 code today...

[roadsession]

So the car pulled a P0456 code today "Very small evaporative system leak"

Can I assume this is just a loose gas cap that I needed to tighten? Looking for most common reason for this code.

I cleared it today. IF it is not a loose gas cap and it's something more - when should the check engine light return?

Thanks

[Loren]

P0456 Fuel Tank Ventilation System (Minor leak) - Below Limit

Possible fault cause

- Tank cap seal

- One or several leaks in fuel tank ventilation system

Check the o-ring on the gas cap too.

In a few rare cases the EVAP canister purge valve cracks or leaks.

[roadsession]

P0456 Fuel Tank Ventilation System (Minor leak) - Below Limit

Possible fault cause

- Tank cap seal

- One or several leaks in fuel tank ventilation system

Check the o-ring on the gas cap too.

In a few rare cases the EVAP canister purge valve cracks or leaks.

Loren - thanks for this.

You don't happen to have a part number handy and a place I can buy a replacement gas tank cap do you?

Thanks!

[Loren]

P0456 Fuel Tank Ventilation System (Minor leak) - Below Limit

Possible fault cause

- Tank cap seal

- One or several leaks in fuel tank ventilation system

Check the o-ring on the gas cap too.

In a few rare cases the EVAP canister purge valve cracks or leaks.

Loren - thanks for this.

You don't happen to have a part number handy and a place I can buy a replacement gas tank cap do you?

Thanks!

US car?

If so, use 996.201.241.03 Fuel tank cap w/ clip -- US MSRP $13.07

or

go all out with the optional aluminum look cap 997.201.980.00 -- US MSRP $163.39

[roadsession]

P0456 Fuel Tank Ventilation System (Minor leak) - Below Limit

Possible fault cause

- Tank cap seal

- One or several leaks in fuel tank ventilation system

Check the o-ring on the gas cap too.

In a few rare cases the EVAP canister purge valve cracks or leaks.

Loren - thanks for this.

You don't happen to have a part number handy and a place I can buy a replacement gas tank cap do you?

Thanks!

Wait I think i found it.

The car is an 02. maybe I will just replace this as a preventative

http://www.bestsourceautoparts.com/partsCa...ageFrom/catalog

[roadsession]

So I ended up replacing the gas cap.

The old one had a lot of cracks and splits in the Oring. TERRIBLE quality.

Does anyone have hints how to reinstall the strap?

Thanks

[tac27]

P0456 Fuel Tank Ventilation System (Minor leak) - Below Limit

Possible fault cause

- Tank cap seal

- One or several leaks in fuel tank ventilation system

Check the o-ring on the gas cap too.

In a few rare cases the EVAP canister purge valve cracks or leaks.

Experienced this code and tried a new gas cap; just got the code again this past weekend.

Is there a method by which I can isolate which part of the ventilation system is leaking or just 'pick-and-replace' until I get the right one?

Tim

2003 996 C2 Cabriolet

Edited September 23, 2013 by tac27

[Loren]

There are some other tests you can run with Durametric, a PST2, PIWIS tester to further diagnose the problem area.

[tac27]

There are some other tests you can run with Durametric, a PST2, PIWIS tester to further diagnose the problem area.

Loren,

Could you please tell me which test I can run with the Durametric and what I should be looking for? I ran everything I saw that looked remotely linked to the fuel system. Biggest challenge is I'm not familiar with what I should be looking for to detect a leak.

[roadsession]

There are some other tests you can run with Durametric, a PST2, PIWIS tester to further diagnose the problem area.

Loren,

Could you please tell me which test I can run with the Durametric and what I should be looking for? I ran everything I saw that looked remotely linked to the fuel system. Biggest challenge is I'm not familiar with what I should be looking for to detect a leak.

I would take it to your local Porsche shop and tell them that you've replaced the gas cap but you suspect a leak in the fuel tank ventilation system.

If they have a PIWIS they can do a leakage test and pinpoint the problem - a frequent culprit is the fuel tank ventilation system which

If you are a DIY person read this: http://www.pelicanparts.com/techarticles/Porsche-996-997-Carrera/106-FUEL-Replacing_Your_Fuel_Line_Vent_Valve/106-FUEL-Replacing_Your_Fuel_Line_Vent_Valve.htm

Edited December 3, 2013 by roadsession

[tac27]

There are some other tests you can run with Durametric, a PST2, PIWIS tester to further diagnose the problem area.

Loren,

Could you please tell me which test I can run with the Durametric and what I should be looking for? I ran everything I saw that looked remotely linked to the fuel system. Biggest challenge is I'm not familiar with what I should be looking for to detect a leak.

I would take it to your local Porsche shop and tell them that you've replaced the gas cap but you suspect a leak in the fuel tank ventilation system.

If they have a PIWIS they can do a leakage test and pinpoint the problem - a frequent culprit is the fuel tank ventilation system which

If you are a DIY person read this: http://www.pelicanparts.com/techarticles/Porsche-996-997-Carrera/106-FUEL-Replacing_Your_Fuel_Line_Vent_Valve/106-FUEL-Replacing_Your_Fuel_Line_Vent_Valve.htm

Thank you roadsession.

I would prefer to learn how to find the leak with the Durametric, which I purchased so I wouldn't have to take the car to the shop.

Again, if anyone is familiar with how to do this with the Durametric, I'd really appreciate it if you could share that process.

[JFP in PA]

There are some other tests you can run with Durametric, a PST2, PIWIS tester to further diagnose the problem area.

Loren,

Could you please tell me which test I can run with the Durametric and what I should be looking for? I ran everything I saw that looked remotely linked to the fuel system. Biggest challenge is I'm not familiar with what I should be looking for to detect a leak.

I would take it to your local Porsche shop and tell them that you've replaced the gas cap but you suspect a leak in the fuel tank ventilation system.

If they have a PIWIS they can do a leakage test and pinpoint the problem - a frequent culprit is the fuel tank ventilation system which

If you are a DIY person read this: http://www.pelicanparts.com/techarticles/Porsche-996-997-Carrera/106-FUEL-Replacing_Your_Fuel_Line_Vent_Valve/106-FUEL-Replacing_Your_Fuel_Line_Vent_Valve.htm

Thank you roadsession.

I would prefer to learn how to find the leak with the Durametric, which I purchased so I wouldn't have to take the car to the shop.

Again, if anyone is familiar with how to do this with the Durametric, I'd really appreciate it if you could share that process.

The Durametric can tell you that you have a leak, finding it requires other diagnostics (smoke machine, individually testing various devices with a handheld vacuum pump, etc.). The Durametric is like a compass rather than a GPS, it can point you in the correct direction, but it cannot always pinpoint what needs to be addressed; that is up to the diagnostic skills of the operator.

As Loren already pointed out: "P0456 Fuel Tank Ventilation System (Minor leak) - Below Limit Possible fault cause - Tank cap seal - One or several leaks in fuel tank ventilation system Check the o-ring on the gas cap too. In a few rare cases the EVAP canister purge valve cracks or leaks."