toliver5176

Hello new here. I have a 2001 F150 4.2L v-6 with 100K miles on it. Yesterday, while driving home, it started running really rough. I pulled the codes and besides the obvious cyl misfires, I have a P1518.( Intake Manifold Runner Control Fault - Stuck Open) I have done some searches on here and haven't found a definate answer. Is the IMRC vacuum controlled on this model or an electric solenoid. I am not sure where to start on trying to figure this problem out. The problem started all of a sudden and hasn't ran decent since this began. I briefly searched for vacuum leaks and found nothing and ran a can of SeaFoam directly intake the throttle body with no changes. Please help.

wrenchheadk

Take a look at the front of the intake...there should be a little rod sticking out. on this rod should be a little white plastic clip. it's probably broken. the dealership sells them for about .53 cents each. it may be on the back of the intake instead of the front. we see these all the time at my shop.

toliver5176

Well I fixed the IMRC problem. It was, like you all said, a broken clip. But, the IMRC is electronically controlled and is at the back of the motor, below the phlenom. It was kindof a mess to take apart and fix. But that is fixed and I currently have no codes, but the motor still runs awful. Its very rough at idle and up through the rpms

Let me give you some background info. When the motor started to suddenly run bad, the code appeared and i immediately noticed a terrible exhaust leak directly infront of the muffler. Intitally I changed the coil, plugs, and wires and then when I discovered the code, I concentrated on the IMRC and left the leak alone, but know that the IMRC is fixed and the truck still is running rough with no codes, its all I have to go on. I also just noticed that one of the catalytic converters was glowing red hot. What is this a symptom of; could this cat be revealing my existing exhaust leak or could I have a different problem altogether. In addition to the IMRC repair I also changed the PCV and check for vacuum leaks. Help!!!

Just call me Sean

I think one of the catalytic converters may be clogged up.

lonairos57

Hi I'm new to this forum. Looking for the help on how to install the clip mentioned that attaches the runner control rod to the valve lever. Do I need to remove the intake manifold to gain access. I can't seem to see the electronic controller or the control rod, but I can reach and feel them and the rod is disconnected. BTW I have a 1999 4.2L. THX in advance for any assistance.