Car failed MOT?

This could mean the trole bore is dirty and needs service. Here is a guide to help you clean the throttle bore, also the engine needs to be tuned up if it has not been done recently. Once other thing is a vacuum leak which the test should be done when the engine is cold. Here are three guides to help us fix the problem:

https://www.2carpros.com/articles/throttle-actuator-service

and

https://www.2carpros.com/articles/how-to-tune-up-a-car-engine

and

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please run down these guides and report back.