Question

1999 Chevrolet Tahoe 5.7L with engine code P0405, what should I check first?

Answer 1

Hi there,

I would start by removing the egr valve and cleaning it up with some carb cleaner. If the egr valve is sticking then you will get a code from the position sensor. You will also need to check that the egr tube is clean. Sometimes they will clog up with oil and carbon, you will get this same code. Finally, make sure you are getting vacuum to the egr valve when you snap the throttle. If not, then check the egr solenoid. It may not be working at all.

Answer 2

P0405 CHEVROLET Code - Exhaust Gas Recirculation Position Sensor Circuit Low Voltage

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