I have 1997 Mercury Villager. I recently had a water leak from a hose under the upper intake manifold (plenum). I removed the upper intake manifold, replaced leaking hose and reinstalled manifold with new gasket and blue RTV. I had trouble getting it to crank, but it finally cranked but was idling “funny” and threw the code P0505 (Engine Idle Air Control). I checked the IAC valve with an ohm meter and checked out. I took the manifold back off and reinstalled to make sure that it was sealing well and not getting an air leak through the manifold. The vehicle was running fine before I took it apart but now it is not drivable. Please help, the van has been down for 3 weeks and I don't know what else to do.

 

Not to sound demeaning, but are you sure all the wires are hooked up properly, sometimes a plug can be put on crooked and it won't run right. Also if a ground was not attached it will act funny. I also find that sometimes on the newer cars I work on I need to disconnect the battery for up to 24 hours to reset the computer then it works. And some don't work until you put 100-500 miles on them and I guess it sorts itself out. I would try some of these simple things then do the code test again to see what comes up. If this stuff does not work let me know and I will do further investigation.

 

I double checked all of the electrical connectors and vaccum hoses and I left the battery disconnected overnight after I reinstalled the manifold before I tried to start it the next morning.

 

Ok, had to make sure, some people don't do that. I will get back to you to see what I can find out.

 

Okay, thanks for the help. I will check everything, again to make sure that I did not miss something.

 

Ok, when you turn the key to the on position do you hear the fuel pump kick on? If so maybe something else was causing to run poorly, I know when I run codes sometimes the part it says is bad is not bad and is something else in the circut. Maybe you have a bad MAF sensor or O2 sensor? If it has a dist cap make sure it's not corroded, many times they get replaced with aluminum ones and they corrode quickly. If I recall correctly these minivans had issues with fuel pumps as well, like they work but are not pumping enough fuel so it starts hard and does not stay running when warmed up.

 

I hear the fuel pump kick on, but I will check it for adequate pressure.