Stupidly left fuel cap open does it matter

[robdex1]

Was in a rush putting petrol in and somehow forgot to put the cap back. Noticed after driving about 30 mins in the rain that I could see the tank open in the mirror and I hadn't screwed the cap back in either. No idea how I did that never done it before. Is there any reason to be worried?

[Wacky Racer]

Where is the cap?

Probably will be OK if the car is running fine,

Easy mistake to make.

[Lincsls1]

I don't think I would be too concerned.
You could always bung a moisture absorber in the tank as a precaution
Example:
https://www.amazon.co.uk/Wynns-71867-325ml-Dry-Fue...

[2 sMoKiN bArReLs]

robdex1 said:

Was in a rush putting petrol in and somehow forgot to put the cap back. Noticed after driving about 30 mins in the rain that I could see the tank open in the mirror and I hadn't screwed the cap back in either. No idea how I did that never done it before. Is there any reason to be worried?

I've done it quite a few times with no ill effect.

[robdex1]

Wacky Racer said:

Where is the cap?

Probably will be OK if the car is running fine,

Easy mistake to make.

Left hand side of car at back. Honda jazz 2008

[Lo-Fi]

robdex1 said:

Wacky Racer said:

Where is the cap?

Probably will be OK if the car is running fine,

Easy mistake to make.

Left hand side of car at back. Honda jazz 2008

I think Wacky meant have you still got the cap or is it now still sitting on the petrol station forecourt?

[Blue Oval84]

It'll be absolutely fine I'm sure.

[Zarco]

Lo-Fi said:

robdex1 said:

Wacky Racer said:

Where is the cap?

Probably will be OK if the car is running fine,

Easy mistake to make.

Left hand side of car at back. Honda jazz 2008

I think Wacky meant have you still got the cap or is it now still sitting on the petrol station forecourt?

It was still at the petrol station when I did it.

[DavePanda]

You'll get more moisture in the tank from condensation than from leaving the cap off