Then the solenoid is your problem. Normally air should pass through. When it is grounded (through the pressure sensor on the intake) it closes and prevents boost from getting to the injection pump.

Take it off the car and spray some carb cleaner through it. Actuate it a couple times to be sure it works properly. You want the protection system working.

-Jason

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1991 350SDL. 230,000 miles (new motor @ 150,000).

Tesla Model 3. 136,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.