Rough Idle Caused By EGR Sensor Sticking on Ford Expedition

Problem Description and Possible Solution

The Ford Expedition is known for intermittent rough idling, which may be accompanied by illumination of the check engine light, and poor fuel mileage.

This may be caused by the EGR sensor sticking, causing the EGR valve to stay slightly open, and diagnostic testing must be conducted.

The EGR valve and sensor must be replaced together to correct this concern.


Problem Data
RepairPal Verified
Average mileage: 175,349 (98,000–278,471)
Exhaust & Emissions affected: 5.4L V8
10 model years affected: 1997, 1998, 1999, 2000, more2001, 2002, 2003, 2004, 2006, 2007
70 people reported this problem
Viewing 1 - 20 of 20 comments
I changed the IDLE AIR CONTROL VALVE THE SAME PROBLEM EXSISTS idle only with pressure on the gas dies out when foot is off the gas.sounds accure when engine is off crackling noise and strange oder.
When warm only it idles rough, drives / performs normally, just a very rough idle. Replaced fuel filter, fuel pumps, coils, plugs, cleaned injectors (by hand, individually), IAC valve, problem persists. All parts were Ford parts. Modifications include 6 pound lower pulley, Bassani CAT back exhaust, and a cold air intake with a K&N filter, and was dyno tuned at the time of modifications; the problem does not coincide with the modifications, truck ran fine with these mods for 150,000 miles. What gives? I guess the EGR valve is next on the list.....
Tough time starting it, And it idles rough. Can't go over 40-50 mph... It bogs out and if I try to give it more gas, it wants to die.
Rough idle, wants to die out, especially when I turn the wheel all the right. Giving two codes po156 and po156 I think one is for mas air flow and the others is o2 sensor after cat. Exhaust pipe leaking right before muffler and sound like something is rattling I side it
random rough idle not related to any one cylinderor firing order. seem to run fine on acceleration but has some hesitation at shifting rpms. will check out egr and sensor vacuum hoses fist then to replacment parts as needed. thank you all for ypur imput.
Engine oscillates between 500 and 1200 at idle. When decelerating the rpm will hand at between 1400 and 2000 then bleeds off to norm after a short period. When I put it in gear RPM builds to about 2000.

Acts it wants to die when its idling. Will die sometimes at a complete stop. You have to keep one foot on brake amd one on the gas. Replaced egr and some other small valve. Still doing it.
we have ford expidition 10 to 15 menutes running the engine will stop ,and start again run and thin stop very difffecult to me , and the instrument panel ,no miles edge found only doted green light only. and turning the key to off and on will come back
Replaced idle air intake valve but Expedition is still running rough (low idle). It is running better but still sounds like it's sputtering and/or low idle.
When I'm in a park position the RPM gauge revs a little making the engine shake. When I put the vehicle and to Dr it begins to excessively rev in between 500 and1000 RPM
Check engine light was on! Codes read misfire#3, EGR, !!! We replaced. New EGR n idle air flow value, n plugs! Fuel pump n fuel filter n still not fixed!!! But no codes are reading!
Vehicle was running fine,.went to the store, approx. 5 miles, i was running the air, on the way home it starts chugging on a hill and does it all the way home, but more noticeable on hills, haven't gotten it fixed yet, just happened, so I'm searching for ideas of what it could be and how much it might cost to get it fixed.