if it's locked up in a shed then you got no ventalation and leaking fuel.

Now you got potential to blow up the shed as well - get Mobile Mechanic or tow turck to workshop!!!!

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Funny looking German Subaru

nah aint that stupid bro, it only leaks when the car turns on! We have tried to look for the leak but have had no luck! its seeems to be internal!

yeh figured you would use some common sense but fuel vapour in an enclosed space can be just as bad mate! One spark and kabooom.

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Funny looking German Subaru

if its internal i'd be looking at injectors...
many years ago i had a VN crapodore that had been left sitting for a few years...
i did an oil change, left it a few weeks, went to go for a drive and oil light came on.
turned out that an injector was gummed up in the open position and then the fuel pump kept pumping fuel into the engine, which seeped past the rings and thinned all my new oil down...
scary shit when you pull the dipstick and its way high with oil and stinking of fuel!!!