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Hi. I have recently had this car to the local garage twice to deal with a petrol vapour smell. The first time they replaced the fuel filter and associated rubber hoses which were cracked and weeping. Some improvement. Still a petrol smell though so on investigation they found some petrol seeping from an injector seat / seal. so they replaced all six seats. The garage owner and head mechanic agree with me that there is still a vapour smell (enough to enter car via ventilation system). They are scratching their heads for a cause as no visible leaks from injector seats and all rubber hoses now replaced. Any thoughts or advice please?

If it's a raw fuel smell but no obvious signs of leakage in the engine bay or from the fuel filter, perhaps the fuel tank area would be the next place to check. The seal around the fuel gauge sender unit is a possible cause, or else the breather system and associated hoses and pipes. This would be especially so if the smell is more prevalent when the tank is full or at least over half full.
(I'm assuming the fuel cap and seal are correct for the vehicle and in good order).

The smell is difficult to locate but seems to be coming from the area around the rear fuel rail or around the phlenem chamber. It only happens when the car is running and gets worse as it warms up. I don't think it's anything around the tank area. The garage has mentioned looking at the charcoal filter ?? in the new year. Just seems odd that all of a sudden I could have not one but three sources of raw petrol smell suddenly appear.

?? No other thoughts? Do you think they are on the right track looking at cannister etc or would it make more sense to have another better look at the injector seats?

To be honest, any of these things could be the source of a fuel smell, so only someone looking at the car can really provide definite answers. However, if fuel is leaking externally, there would be some evidence of wet fuel or a fuel residue, so if there's no evidence of this, then it seems unlikely to be the fuel rail or seals, so they could very well be on the right track.

Does the fuel tank have a breather pipe that has become kinked or partially blocked? When the pressure rises enough to force the fumes through there might be a larger volume than usual hence easier to smell.

Thanks for the suggestion. I'll check it out.