I had water leaking into my rear passenger footwear for a few weeks and tries tracing it myself with no joy.

Had it in at my local ford dealership yesterday for a diagnosis.

After stripping th car down and checking the usual places, they found that my car had been in an accident entirely before I owned the car and had the rear quater panel replaced.

The place water is getting in was along part of the weld for the quarter panel ( under the plastic trim on the roof) . Apparently there's a small crack in the weld but the won't take it any further now they know its been damaged.

The mechanic advised me to use a decent automotive sealant along the cracked seem to stop the ingress.

Any recommendations for this would be appreciated.

Is it definitely this and not in the boot where the spare tyre well is? This is extremely common in the MK3 if that's your model. Check the tyre well for standing water. It ends up all underneath the carpet in the rear foot well. Lots of threads on here... Search for MK3 boot leak

Yes mate, 

100% now, I had checked this myself first,

The ford mechanic also told me it was the first thing he checked as he gets it almost weekly,  although he said ford don't own up to it being a common fault. They took the back bumper off and checked those 4 vets and checked inside for any water too.

He said the had put cameras inside the body to see where water had been tracking from and it all stems from this seem on the roof. 

10 hours ago, JPW said:

Is it definitely this and not in the boot where the spare tyre well is? This is extremely common in the MK3 if that's your model. Check the tyre well for standing water. It ends up all underneath the carpet in the rear foot well. Lots of threads on here... Search for MK3 boot leak

Yes mate, 

100% now, I had checked this myself first,

The ford mechanic also told me it was the first thing he checked as he gets it almost weekly,  although he said ford don't own up to it being a common fault. They took the back bumper off and checked those 4 vets and checked inside for any water too.

He said the had put cameras inside the body to see where water had been tracking from and it all stems from this seem on the roof. 

At least you can focus your attention on that area then!