Took my car to a Tesco hand car wash. Something was used on aluminium step boards and it has marked them. It looks like milk running down them. Noticed this before leaving car park and took it back. They denied that they had caused the damage. Spoke to Tesco and they informed me that it was a franchise and to take it up with the Company. The car wash cleaners wear a Tesco uniform and it is advertised as a Tesco hand car wash, in their car park and also on the Tesco website. I have been to,d that they only use Autoglym products. Autoglym have tested their products on my car and say that it s not their product that has caused the damage. Any idea who I should take this matter up with please.