Tesla is suing a German car parts maker for failing to produce the falcon wing doors of the Model X SUV.

The company, Hoerbiger Automotive Comfort Systems LLC, apparently misrepresented its ability to design the advanced doors which forced Tesla to find a new supplier, ultimately delaying production and deliveries of the Model S.

The federal lawsuit asserts that Hoerbiger was selected from a number of other companies but between February 2014 and May 2015, was unable to produce a prototype able to pass Tesla’s strict engineering standards. This lead Tesla to cut ties with the company in May last year.

It’s claimed that the prototype falcon wing doors from Hoerbiger leaked oil, sagged and produced excessive heat. The German firm says that it is owed money for the work it did, in addition to the $3 million it was already paid by the electric automaker.

In an email sent to The Wall Street Journal, a Tesla spokeswoman said “We were forced to file this lawsuit after Hoerbiger decided to ignore their contracts with us and instead demanded a large sum of money to which they are not entitled.”

The lawsuit goes on to say “Tesla incurred millions of dollars in damages, including, but not limited to costs of re-tooling the entire vehicle in order to support a different engineering solution.”

PHOTO GALLERY