Knock knock.
Who's there?
Ford.
Ford who?
Ford'a next act, I'll do some car knock knock jokes.

Knock knock.
Who's there?
Datsun.
Datsun who?
Datsun unusual name for a car.

Knock knock.
Who's there?
Beemer.
Beemer who?
Beemer Valentine.

Knock knock.
Who's there?
Camaro.
Camaro who?
Camaro here. I wanna be near you.

Knock knock.
Who's there?
Honda.
Honda who?
Honda first day of Christmas my true love gave to me...

Knock knock.
Who's there?
Accord.
Accord who?
Accord a cold last week.

Knock knock.
Who's there?
Acura.
Acura who?
Acura cold with chicken soup and orange juice.

Knock knock.
Who's there?
Sciracco.  (I'm not sure how to spell this VW name)
Sciracco who?
Sciracco if you want to stay home.

Knock knock.
Who's there?
GM.
GM who?
GM glad I met you.

Knock knock.
Who's there?
Hyundai.
Hyundai who?
Hyundai my prince will come.

Knock knock.
Who's there?
Opel.
Opel who?
Opel-ease! No more car knock knock jokes!