Q: P0401 keeps coming on, already done, cleaned carbon, egr replace, egr tube, pigtail harness.

asked by on September 27, 2017

I have replaced the egr, egr tube and pigtail. I also cleaned out the port by the intake manifold, and replaced the throttle body gasket. Light keeps coming on as p0401. 3rd get and 2nd wire harness.

My car has 140000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. There are many issues that can effect the EGR system. You have looked into most of them, but may need to take a second look. For example, you need access to the inside of the throttle body to clean the carbon that will effect the EGR system. If you did not get into it deep enough, you did the EGR system no good. Secondly, you need to look into the vacuum source, and make sure none of those lines are damaged or clogged. For more help with diagnostics and repairs, contact our service department to schedule an appointment.

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