Unleaded Fuel in Deisel Engine

A 2006 VW Jetta TDI with 32,000 miles. Unleaded regular gas in diesel engine.The dealer dropped the engine, drained the gas replaced the fuel filter. The car starts, drives fine, but refuses to re-start. Why?

Do you mean it refuses to re-start when warm or do you mean it started once and no more? Do you mean he dropped the “tank?”

If it was driven unit it quit, that is not a good thing. The pump and the injectors could both have been damaged as they rely on the lubrication of diesel to run and gasoline does not have it.

Assuming it started and ran, how far was it run before it was turned off or failed? There could have been gasoline in the lines if they were not purged.

OK On the brighter side, it could be nothing more than air in the fuel lines. Diesels don’t like that and trying to get all that gas out could have very easily ended up with air in the lines. Easy cheap fix.

If I’m reading this right it was running fine, got you home or something, and now cranks over but will not start?
Maybe a fuel shut-off solenoid unplugged or inoperable?

Also a bit curious about how much gas was put in and how long it was operated like this.

If that’s the case, I would vote for a loose fuel line connection someplace that let some air into the system (maybe the replacement filter).