Changing the oil.

Darren knew his parents would go off their head if they knew he had crashed his car whilst racing with his friends especially seeing they were the ones paying for his insurance.

He put his car in for repair and told them it was going in for a service.

But when the repair bills started to mount up he knew he would not be able to pay it without their help which meant telling them what he had done.

But luckily or unluckily for him depending on how he looked at it it did not come to that as the mechanic had another way he could pay for it which just involved putting on a bodysuit which he guessed many people had used before him and service the mechanics needs.

Which to him at that time seemed the better deal then telling his parents.