My engine light is on and has code PO401. I had previously replaced egr valve assembly. Now light is back on and it reads egr insufficient airflow. 99 T/C 3.3. Can someone tell me what I need todo to fix problem.

 

get a better part

 

Check the hoses too.

 

Thanks, I am going to check the hoses first to make sure there is no leaks. Does the hose that connects the air box to the motor have anything to do with this problem.

 

P-0401 EGR SYSTEM FAILURE

POSSIBLE CAUSES
EXHAUST LEAK
INTAKE MANIFOLD RESTRICTED
EGR BACK PRESSURE TRANSDUCER DEFECTIVE
EGR VALVE ASSEMBLY DEFECTIVE
EGR VALVE ASSEMBLY MOUNTED INCORRECTLY
EGR SYSTEM FAILURE DOES NOT REOCCUR
EGR TRANSDUCER LINE BLOCKED
EGR VALVE ASSEMBLY DIAPHRAM DEFECTIVE
VACUUM SUPPLY TO EGR SOLENOID INADEQUATE