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Q: EGG code p0400, multiple cylinder misfire, removed and cleaned egr and pipe with no change

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Egr code p0400 muktiple cylinder misfire, removed and cleaned egr and pipe with no change My car has 195000 miles.
My car has an automatic transmission.

A: Hi there. The P0400 EGR (exhaust gas recirc...

Hi there. The P0400 EGR (exhaust gas recirculation) valve code may not be a valve not working. This code description is a EGR flow malfunction. The fact that your vehicle has multiple cylinder misfires leads me to believe the valve may be stuck partially open.

Try removing the EGR valve and blow through the passage. If air flows, replace the EGR valve. If no air flows, it may be a control issue. This would require a scanner to monitor parameters and circuit tests to be performed. I recommend having your vehicle’s EGR code P0400 be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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