Passat PHEV old fuel question

[Wackywoo105]

My Passat PHEV was delivered in Feb 26 and hasn’t visited a petrol station since and it still doesn’t need to. How long will the fuel last, and how will I know if it’s starting to go bad? When I eventually refill, should I add a fuel stabiliser, and if so, which one?

Just to add: I originally posted this in the Other Marques → Audi, Seat, Skoda & VW section, but I don’t think I’m going to get a reply. I’m also not convinced it belongs there, so apologies if this isn’t the right place either.

[ashenfie]

Technology the petrol past its best. I would keep quarter of a tank max if your driving short ranges

[Stevemr]

I regularly leave my motorbikes for 5 months over winter with fuel in them. But I do make sure it’s e5 fuel. Never have a problem.

[larrylamb11]

In a modern fully sealed fuel tank system the fuel will take literally years to go off. Even then, modern fuel injection will still run with fuel that's gone off - it has to be pretty bad before they won't run. Evaporation of the volatiles is what makes fuel go off and the evaporation is limited in modern fuel systems by far bretter breathing and vapour management.
For a modern car like yours, you really won't need to worry about it.

[xx99xx]

larrylamb11 said:

In a modern fully sealed fuel tank system the fuel will take literally years to go off. Even then, modern fuel injection will still run with fuel that's gone off - it has to be pretty bad before they won't run. Evaporation of the volatiles is what makes fuel go off and the evaporation is limited in modern fuel systems by far bretter breathing and vapour management.
For a modern car like yours, you really won't need to worry about it.

I agree.

Had a similar car during lockdown and didn't need to fill up for about 6 months. Even then, my version of filling up is going from half full to full as I never go below half if I can help it.

Old fuel still works. It's not like your on a competitive race track.

[Teflondon]

My Passat did 1800 miles on electric before I put more fuel in. On the tank iits around 400 miles for petrol.

How you finding your Passat? Mines rubbish, brakes are crap, the car jolts when leaving my house within a minute or so quite often. I'm gonna end up early terminating the lease because I can't stand it.

I'll avoid another plug in hybrid with a dsg box.

[xx99xx]

Teflondon said:

My Passat did 1800 miles on electric before I put more fuel in. On the tank iits around 400 miles for petrol.

How you finding your Passat? Mines rubbish, brakes are crap, the car jolts when leaving my house within a minute or so quite often. I'm gonna end up early terminating the lease because I can't stand it.

I'll avoid another plug in hybrid with a dsg box.

If it helps, my 2017 Passat GTE was perfect for the 6 years I had it. Would've been happy to keep it but had to change because of the lease scheme.

Can't really comment on the brakes - they worked. What's not to like.

Jolts - none really. The transition from petrol engine to electric motor was seamless as it should be. DSG has been amazing in all the cars I've had it in.

[hidetheelephants]

What does the manual say on the subject? That's the first place you should look for information on fuel management with a hybrid. AIUI manufacturers of hybrids generally include routines in the ECU software to test-run the engine periodically to keep everything operational even when users are running for long periods solely on battery.