P0402 Ford -

Question

97 ford explore 5.0. Checked egr with vac pump, opens and closes fine. Change dpfe sensor that is on back off intake that has the 2 hoses that go to egr now truck runs like its misfiring and has p0401 and p0402 code. Could this happen if hoses are crossed or is this something other than those 2 parts?

Answer 1

HI there,

This can happen if the hoses are crossed, but also, check and make sure that the egr solenoid isn't allowing the egr to pull vacuum when it shouldn't be. These only kick on at high engine rpms, not at idle. Disconnect the vacuum line from the egr and see if the truck runs normally, if it does, then it's possible the egr is getting vacuum when it shouldn't.