Hi, I've been struggling with a 401 code restricted EGR flow. I replaced the EGR valve, DPFE sensor, EGR relay and EGR tube and had the ports cleaned. Now I have a 402 code excessive EGR flow. What happened? A friend of mine says that the DPFE sensor that I bought at the parts store may be bad. He suggested that I buy one from Ford and replace it. I need to pass an emmissions inspection in July.

Any suggestions ?

It's a 97 F150 with a 4.6L with 140,000 miles.

Thanks,
Tim

 

If it's not the sensor, it could be a sign of partially clogged cat converters.