Faulty car on hire purchase

Unitedwestand_2

Long story short. Son bought a car on HP after 3 months car developed a fault serious enough for it to require a new engine. Finance company's own mechanic confirms this and that it was sold to my son with the fault already existing. 
So, for nearly a month my son has been without a vehicle and reliant on borrowing his brother's van to get to work etc. My question is,is there any compensation he could claim for this inconvenience and if so who could he claim off?
PS. He is still paying his HP payment as he doesn't want to harm his credit rating even though he is not using the vehicle. 

[Deleted User]

What does the HP agreement say?

He could very likely claim from the company he bought it from for a hire car if they can't provide a loan vehicle. Who is it?

Unitedwestand_2

Hippo motor group, Blackburn 

Herzlos

What did Hippo say/do about it? Where is the car now?

Unitedwestand_2

The car is at an independent garage, where it was towed when broken down. 
Hippo have,been fobbing my son off every time he contacts them. Promising someone will get back but no one ever does 

[Deleted User]

Ideally he would have dumped the car on Hippo's forecourt and told them he was rejecting it, but the time has past.

What does the contract say?