I got this 2003 XLT Supercab 4.6L in August and noticed the idle problem then but I have not been able to fix it yet... I have no pending codes, no CEL, changed the fuel filter, air filter, IAC, and started looking for the ECT sensors...

I have good fuel pressure and the engine runs great but for the warm/hot idle which is a bit shaky...I am also looking at the scans I made of the ECU to see if I have a dying O2 sensor or something I am missing...

Any ideas will be appreciated...BTW I am changing plugs and COPS this weekend...

 

Let everybody know if the cops and plugs fix the problem!!!!!!!?????? If the cops and plugs dont fix it ,,,, i would suggest driving it until CEL comes. Then you wont be chasing your tail!!!!!!!!

 

While you are at it, clean the MAF and remove and clean the throttle body and EGR ports.

Should be a write up in the DIY's. The 4.6's like to goober up the EGR ports.

 

That is just it... I have driven this truck since Aug 2012 and the CEL does not come on and yes it does work; I also have no pending codes either...In my Explorer there are 2 ect sensors...One for the PCM and one for the temperature gauge... I am not finding the same setup on the F150 or at least the parts stores are not aware of but one ECT...

The EGR valve is promising...Since the valve is not open at idle[not supposed to be open] if I have vacuum opening it that could cause the shaky idle...

And I have cleaned the MAF sensor twice; when I first got it and second when I replaced the paper air filter with a K&N...I also cleaned the tbody and inside the intake manifold too... Both were not pristine but not filthy either...


Thanks for the ideas... Please keep them coming...I will resolve this problem...

 

So egr valve; my question is can it be cleaned to be equivalent to a new one? or is a new one a good spend? cuz im going legit not hillbilly i want a new top end... youd understand if you knew who had it for the last 3 years.. when it needed a tuneup it got super neglected so here i am.. ressurection time... im gonna clean TB I replaced IAC i have a new air charge temp sensor soon to go in when i get home. NOW for this egr valve.. i just want a motocraft oem.. if i go that route what else should i clean or replace to justify a new EGR-V? also i have 2 inches plus of slack on my throttle cable.. bad bad..

 

Also wanted to say min is opposite rough low idle at 1200 rpm a little rough and then better warm i believe... nut i bet this ever so noticeable deep pulsing vibration.. in the cab i thought it was my neigbors chevy starting up but no it was an ever so slight deep hum that was regularly pulsatingabout every second... hard to explain but no rough idle.. can put me camera on the steering rack while idling and get perfect still video...