I'm having a dispute with my dealer about whether a repair should be covered by the warranty. If I refuse to pay for the repair, can they hold my vehicle until I pay them?

Yes.

If you have a dispute, call the manufacturer, if you bought the car from the dealer new. The manufacturer pays the dealer for the warranty work. Its not like the dealer does the work for free.

If you still have a problem, pay the dealer for the work, keep the receipts and all records you have made on the problem in question, the dealers response, etc with dates, names etc and get legal advice.

I'm having a dispute with my dealer about whether a repair should be covered by the warranty. If I refuse to pay for the repair, can they hold my vehicle until I pay them?

What work has been done and why isn't it covered under warranty?

Normal wear and tear items are not usually covered by any warranty. Failure of a part that was originally installed by the manufacturer due to poor quality or poor design IS usually covered by warranty. However, if an original part was damaged by non-standard parts installed by a dealer, then your complaint would be with that dealer and not the manufacturer. The manufacturer will only repair original factory items. Any add-on's, such as what some sales departments do to sell a car, i.e. non-standard shocks or suspension wouldn't be covered by any factory warranty. Why?...because it isn't a factory part.