New to forum. Hello to all.

I have a 1997 Ford F-150 4-wheel drive with a 5.4 and automatic it has 140,000 miles and has been a excellent truck. The service engine light has been on and it had 2 codes 1: P0401 EGR flow insufficient and 2: P0402 EGR flow excessive. Can anyone possibly point me in the right direction to repair this problem. Thank you for any help.

 

I would use a vacume pump and atach it to the egr valve pull a vacume the engine shoud seam like there is a load, if this happens replace the DPFE sendor, this a black square or rectangle with 2 tubes that hooks to the egr tube from the manifold. this sensor is a common ford issue.