Hey guys, I have a 98 f150, 4.2 engine 2wd, just put a brand new engine in it but am getting codes P1537 intake runner control stuck open bank 1 and P1538 which is the same but is bank 2 as well. Obviously it has no power because of this but seeing as you can't get to the damn actuators I pulled the intake plenum off and the vacuum lines ARE hooked up and the linkage arms are hooked up as well and I see no issues, diaphragm isn't bad either and I can manually open and close actuator and manually move flaps with no issues. Nothing looks off or messed up. HOWEVER, on the passenger side of the plenum there are these 2 vacuum purge solenoid looking things, both have 1 electrical plug going to them, and 2 vacuum hoses each. Here's the kicker, 1 of those solenoids has the bottom vacuum nipple broken off and has been sealed up with silicone and the hose that is supposed to go it is plugged off. Does that little solenoid have anything to do with those runners? Or that vacuum hose not being hooked to the solenoid the issue? Do those little solenoids help run the intake runners or what do they do? I thought the only thing that ran the intake runners was the actuators on the back of the intake and that was it? Please help because I can't find any information on this online and its driving me crazy. Also, on the bottom of the plenum, there's about a 1/2 inch stainless steel nipple where a hose should be going to, the hose coming off the evap crap on the drivers side firewall is going to that fitting, is that in the correct spot?? Any input would be greatly appreciated!

 

When I had a P1538 on my 03, the problem was intake plenum gaskets and isolator bolts, the IMRC was working fine. Go figure. Plastic intake.

 

I have p1537 p1538 p0171 and p0174
both imrc are stuck open. 174 is a lean code most likely due to the stuck runners. I had this problem fixed for a year and no codes. The linkage was disconnected. A year later now I'm getting both codes and have no idea how to fix it. I also have a 98 f150. The 98 doesn't have the isolator bolts. My next step is to remove the intake and see of the hoses are bad.