Help ! What's going on ?

Hello everyone,

I own a PFL for pretty much a year now and the RS3 adventure is becoming a nightmare since yesterday.

I was sitting in the car yesterday using VCDS and testing a few diagnostic softwares, and left the car idling for a long moment, probably 30 minutes +.

I started progressively smelling fuel outside the car and discovered a leak behind the right hand tyre.
The panic was real and I instantly shut off the engine. Not even understanding why I pulled the tank cap, hearing a big pressure release that progressively stopped the fuel leak.

The leaking area I identified is basically the active charcoal container or right behind it.

I brought a mechanic to my place and started the car again, but we couldn't reproduce the leak.

Today I started the car I went for a very quick drive around my neighborhood :
- driveability is atrocious, obvious loss of power, under regular load sometimes the car is jerky and I can clearly feel power cuts as engine RPM goes down then back up while the throttle is applied
- idle feels super weird and not very regular, monitored it through vcds and discovered that I was going from low 700 (710) to almost 800 RPM at idle.
- car can be left idling and engine shuts off by itself (happened twice)

VCDS and other softs scan brings no error regarding engine/fuel system issues.

What do you guys suspect ?

Active charcoal container ? Fuel pump ? Fuel pressure regulator ? Purge valve ?


Few additional data :
Nothing under the hood, no leak and no fuel smell on the oil dipstick.
Car is stock, only a few mods like secondary decats, nothing serious.
Service less than 3000km ago, including new spark plugs.

I live in a country where Audi don't even sell Petro A3s, let alone RS models. (all replacement items have to be ordered, it took them a month to bring 5 spark plugs)

I just want to know what I'm up against before taking it there.

Thanks for reading.

Thanks for replying Hal.
I believe it was a pressure release when I opened the gas cap.
It might sound stupid but I had just received diag tools and I was testing a few things like data logs, live data monitoring and didn't realize the impact it would have on the car. It's definitely a mistake.

Plus, I live in Morocco, if I remember it was 26 degrees Celsius when this happened.
I don't have a HPFP.

Until now I wasn't able to reproduce the leak to make sure it's from the active charcoal canister, do you think there's any other possible suspect leaking fuel in that area ? (behind the right hand rear wheel).

Cheers

Thanks for your help Hal.
Trying to contact the dealer to book it in.

AudiNutta said:

Good luck, hopefully they can get this sorted for you. I will keep an eye on this thread to see what you find.

Click to expand...

Thanks I'll update the thread when I'll have a feedback from the dealer.

T-800 said:

Could be that the active charcoal canister is on its way out...

When I had the fuel pump cutting out issue the Audi Assistance guy explained that whilst the car is idling the lift pump in the tank is only getting a very small voltage and on some modules there was a software issue that would cause the voltage to drop to 0.0 thus cutting out the car.

The point I’m making is the very low voltage ensures enough fuel being sent to the hpfp at the front to suit the idle conditions. Once you use the throttle the voltage climbs as it reads demand increase from throttle position.

The only other place that I’ve seen leak is the HPFP sensor fitting, had it on my 8P where it stank of fuel although it’s not in the location you say your leak is.

Click to expand...

I was going to PM you as I read somewhere else that you had a FP issue on PFL.
I think the active charcoal canister is dead anyway, I've read everywhere else that when liquid fuel gets inside the canister you need to replace it as it's made for fuel vapor.
On the brighter side, I think that a leak located by the rear wheel sounds less "important" than something that would be closer to the engine bay.
From my various readings online it could be anything from the EVAP system itself, to the fuel filter, purge valve, fuel pump, etc.

Just got the car back today.
Fuel pump failure, they replaced it + the mechatronic module. It took them almost a month and a half to make a diagnosis and get it fixed.
1300 euros bill + Audi AG couldn't care less even with the history we have (family bought like half a dozen cars in the recent years from them).

Definitely going to competition for my next car, not because of the product itself but everything that comes after the purchase.

Car is out of warranty so I had to pay for everything. I wasn't expecting Audi Germany to take care of it for free, but the tech who worked on my car said they knew about the FP being a new part number for RS3s (+ what we can read online regarding FP failures even on facelift cars).
I was expecting and was okay with the idea of paying for labor and everything with Audi AG providing replacement parts for an okay price, which they didn't.

Being loyal customers doesn't matter to them I guess.

It was 3 years old at the time.

Update : months later, I've just discovered that my high pressure fuel pump was actually never replaced, only the fuel pump modules were ! I found online that there is an actual recall for fuel pump electronics for 2016 RS3s (my VIN number shows 8V5GA, G is for 2016) !
I've basically paid 1200£ for something that should have been done for free, right ?

Is a car out of standard warranty not eligible for free recalls ?

Cheers

Things are getting funny now. I gathered more information about this recall.

It has been officially released worlwide under number 20DB on September 25th 2018, which is 10 days after my first email to Audi Germany reporting the issue (fuel leak, fire risk).

Coincidence ? It might be ..

What do you guys think my next step should be ?

Thanks mate.

Looking at this whole thing now it's a disgusting behavior from Audi AG.
They aknowledged the problem, kept my car for testing and I've been left without even a courtesy car for over a month and I ended up paying for they sh*t.

To all PFL owners, have your FP modules replaced if it isn't already done. When the leak happened the dash was showing absolutely nothing and the ECU wasn't able to record any issue until way after (misfires left right and center due to the failure).