I have a 1999 F150 4.6 145,000 miles. The check engine light came on flashing a code refrencing insufficent egr flow. I then proceeded to clean the ports on the egr housing only to find out that the light came back on. I then replaced the egr valve and dpfe sensor and the light is still on. Anything else I can look for? Your input would be greatly appreciated.

 

You can check the EGR system's physical plumbing by applying vacuum to the EGR valve when the engine is idling. If it starts to stumble from the EGR flow at idle,then the plumbing itself is intact. If that happens you have a controls/vacuum issue. The EVR is an electrical solenoid that controls the EGR valve by passing vacuum through in order to stroke the EGR valve as required by the PCM. That EVR solenoid could be bad,or you might have a vacuum leak on the line feeding the EVR or between the EVR and EGR.
JL

 

Thanks JL, I will give it a try and let you know how I come out.

 

Had the same problem with my 97 4.2. Found out that after replacing the DPFE sensor,and EGR,,the plumbing between the intake assy,and the exhaust manifild was absolutely nasty. My truck was showing 186,000 miles on it at the time.
Also..the DPFE sensors(oem) are prone to moisture corrosion from the vapor,and carbon in the exhaust flow. The new sensors are plastic(not an aluminum alloy)...These plastic ones seem to be resistant to that corrosion issue...lastly,alot of aftermarkey DPFE sensors were built with wider tolerances,and even if good,will throw a code.
Most folks here recommend FORD OEM parts,and while I do concur with that theory,I was lucky. I bought mine from www.rockauto.com and while NOT Ford OEM worked flawlessly until I traded her in on the 07.