Peter Kay this week ruled out writing a third series of the hit BBC One comedy, co-starring Sian Gibson, which concluded on Tuesday night.
He told BBC Radio Manchester earlier this week: "There's not going to be a series three so it won't ever happen. You've got to get out while the going's good. No Christmas special, no."
Peter explained his decision: "You're better quitting while you're ahead. There's only so much you can do in a car and the last thing you want to do is ruin it because I think it's a lovely thing."
"It's been wonderful working with Sian, who's one of my closest friends in the world. We have a good laugh but I think sometimes you've got to just leave things. You need good ideas – that's the problem. You need good strong stories."
He added: "If you're struggling and you just get a sense when you're writing that you might be running out of ideas, that's when I think you should walk away."
Series 2 of the show broke records online this year when the BBC posted all episodes on iPlayer after the opener aired on TV.
But the success hasn't persuaded Peter to change his mind and he's sorry for upsetting people with the decision.
He said today: "I am sorry I have upset people. Sian put her phone on and had about 50 messages.
"She said 'What have you said, my phone's gone mental!?'
"I just mentioned that that we weren't doing another one. That's just the truth. I didn't mean to upset anybody. I didn't think there would be petitions."
You you can catch up on Car Share online here on the BBC iPlayer.