Car in garage for 3 months-full of fuel or empty?

[bull996]

Which is best, or does it not matter?

[CoolHands]

It'll be fine either way. That whole 'petrol goes off' thing is way overdone.

[RDMcG]

I store some cars in the winter. I fill them and use a bit of fuel stabilizer,add some air to the tires, leave the handbrake off and leave the windows open a crack, and cover them. ( Obviously stored inside). TBH for only three months fuel stabilizer not really necessary.

[JAHetfield]

I'd recommend brimming the tank to keep moisture out.

[Snowboy]

For 3 months – it won't make any difference.
Like someone said.
Handbrake off, windows open a tiny bit.

If you think the battery may be old then perhaps wire up a trickle charger.
Flat batteries can make alarms go off and lose memories of secondary blippers – depending on the age of the car.
Or, just disconnect the battery entirely and take it inside.

[E30M3SE]

Mine been hibernating for a month already and will probably remain so until March/April currently sitting with less than 20 litres.

[bull996]

Thanks for the help. I have it on a Ctek maintenance charger, but just wondered about the fuel. I had heard that full is better as it stops moisture building, but then someone else said no, the fuel will go off.

All cleared up now!

[BJT]

I leave my car for three months at a time and always fill the tank up.
It is always nice to have a full tank ready for play time when you get back! Plus, you may save a couple of pounds with the way things are going...

[james_tigerwoods]

I'd be more concerned about the battery....

[craig2003]

I bought my GTO after it being laid up for 5 years, all fluids changed apart from the fuel which was almost a full tank, it got through the MOT, passed the emissions test and run with no problems

[Huff]

Tank empty, esp. if a modern fuel injection system.

3months is around the limit for stability in pump fuels. Petrol loses octane rating, becomes slower burning (can damage cat) and If nothing else, you don't want to pay for 50+litres you drain - waste! - later for fear of gumming-up injectors /carb (yes, it does happen)

Or you can leave the tank near-empty. This means you leave it closed-up with 50-70litres of air in it. From the psychrometric chart you can actually work out how much water vapour is carried in the air in the tank. It's going to be of the order of .... 0.2-0.5grammes. Really; it is that negligible, providing there's no significant airflow though the tank while not used (ie - you leave the filler cap on) If 1/2 gramme of water condenses out - no problem at all.

So I'd leave the tank empty, drain off what remains before chucking in a gallon of new stuff for first restart and you'll be sweet.

[bazking69]

I'd leave it with no more than a quarter, and brim it with some fresh stuff when you put it back on the road.

[nouze]

Mr PhD in car fuellogy said:

Tank empty, esp. if a modern fuel injection system.

Wow, I mean WOW.

[Wacky Racer]

CoolHands said:

It'll be fine either way. That whole 'petrol goes off' thing is way overdone.

Sorry, not true.

The "flashpoint" of petrol goes off after several months. I once bought a motorbike that hadn't been started for several months, it just would not start. Drained the tank, refilled with "fresh" petrol started second kick. Similarly with lawn mowers stored over winter.

In any case a car with a "full" tank is more of a fire risk.

Hence why it's not a good idea to buy petrol from a quiet country garage down a quiet lane which sells 300 gallons a week.

(all imho)

[rallycross]

3 months is not worth even thinking about this!

[jeff m2]

rallycross said:

3 months is not worth even thinking about this!

3 Months in a cold place it is.
Full tank reduces tank condensation.

Fuel Stabaliser for 3 months is matter of opinion, so why not just put it in before its last run. I assume everyone realises it is for the whole fuel system not just the tank. Why risk the alternative!

If my lawnmover and snowblower get "Stabil" I'm certainly gonna dose up my summer cars.
What's the augument, It's a couple of bucks.

[NHK244V]

plastic tank? empty as you like
metal? as full as you can

[CoolHands]

Wacky Racer said:

CoolHands said:

It'll be fine either way. That whole 'petrol goes off' thing is way overdone.

Sorry, not true.

The "flashpoint" of petrol goes off after several months. I once bought a motorbike that hadn't been started for several months, it just would not start.

Sorry, is true.

I leave my petrol lawnmower every winter for several months. It always starts right back up again. Left it for about a year once, & I've never done fk all to it. Started right up. I left my car for about a year off the road, again, started right up again no problem, and no problems since.

[y2blade]

Snowboy said:

For 3 months – it won't make any difference.
Like someone said.
Handbrake off, windows open a tiny bit.

If you think the battery may be old then perhaps wire up a trickle charger.
Flat batteries can make alarms go off and lose memories of secondary blippers – depending on the age of the car.
Or, just disconnect the battery entirely and take it inside.

this^^^

[jas xjr]

Is the petrol tank steel or plastic ? Mine was empty when I parked it up. When I started using the car again it blocked up the fuel filters. Had to change the petrol tank in the end