Anyone know what this is?

[Sp!ke]

I tracked down what I thought was the noise of a sticky tappet to this little chappy.

It says 'LOW' on top of it and has a few electrical cables goig to it and appears to be attached a fuel line. Rather randomly it seems to make an irritating tappetty noise.

See item circled below.

 

[John Jones Jr]

I'd say that is the fuel vapour purge valve. Take it off and clean it out, maybe a shot of brake cleaner might do the trick if it's excessively noisy.

 

[BlackC55]

It is the fuel vapour valve. They do tick and its normal.

 

[Will]

Are you sure it says 'LOW' and not 'MOT' upside-down ?

As said already, it's a valve and they do make a light ticking noise as they operate