Originally Posted by JamesM3M5
Next step is a pressure test of the intake. Also, there is no way to tell whether the turbos are "working" or not just starting the car and running it with no load. You will hear them spinning, but they will spin under any condition unless they're seized.
1) Pressure test intake
2) Check operation of vacuum control system for wastegates. This includes vacuum pump output (at least 20inHg vacuum), all hoses from the pump to the solenoids, and operation of the wastegate acutators themselves.
I have a similar issue, no boost at all and I get a 30FF underboost code. I've checked all visible connections and can't find a leak. I suspect there' something wrong with vacuum system and a wastegate stays open. How can I check if the solenoids work?
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