Hello everyone my name is David, I have been reading the forums for a while now and am part of So Cals landrover club.
I never needed to post anything until now since I am in bit of a pickle.
Our 2004 Discovery 2 is throwing P0505, p0171 and P0174 codes. And I need to smog the car asap so get it registered.
I have swapped out the ICV and nothing changed, then I got a smoke tester and started chasing the leaks. I fixed most of the leaks, I even replaced the pcv baffle in the valve cover. Then I took it to a shop and they told me that according to their experience its the injector seals.
So i replaced the injector seals and to my luck nothing changed. But when I smoke test the car there is a lot of smoke coming out of the passenger valve cover.
So my question is, can a valve cover leak cause these codes??

 

Where do you see smoke coming out of valve cover gasket area? If it's on the top side of valve cover, along inner edge, l'd think it's most likely coming out of the lower intake gasket area. While you had the upper intake off, to replace injector o-rings, did you happen to snug lower intake bolts? Out of the three engines l've pulled, all three had loose bolts, some were finger tight.

Now if you sure it's coming out of the valve cover, which you could verify by pulling hose that goes to upper intake, then l'm not to sure what you have going on, maybe valve seals, valves not seating properly?

 

It's highly recommended to do the PCV modification and get rid of that baffle in the passenger side cover. I don't know if that will help with your current situation, but it can't hurt.

 

its actually coming out of the exhaust side of the passenger valve cover. And its not a little bit either its blowing a lot of air, its whistling and i can feel it on my hand.
I am gonna take the plenum off again to change the valve cover gasket so i will double check those bolts.

 

I have done that on my other D2 and its been great, but this one is just a quick flip so I dont care too much about that lol.

 

Hey guys I just wanted to let everyone know what the fix was.
It was the screw on the bottom of the throttle body butterfly stop. I wasnt the one that figured it out, I took it to a yorks and lancs automotive and they fixed it.

 

Hi Dav, My car is throwing a code P0 505 as well. Can you please tell me how is the screw on the bottom of your throttle body caused the problem??/ Was it a loose crews or missing causing leak? Please let me know. Thank you