So, despite my best efforts: new MAF IACV, PCV, gas cap, and vacuum lines I still toss the 1171 and 1174 codes. Strange thing is that sometimes it will be 1171,1174. Other times it will be 1174, 1171 on my UG.
I don't smell any fuel, but at some point, I'm thinking I will have to pop off the IM and do the injectors while I do the valve covers.

Does anyone have any thoughts to the random nature of the code order?

 

I would get 1174 intermittently (once every couple hundred miles)..... There's a little hole on the top of the intake manifold (btwn the 6 long bolts) that's supposed to line up with something below. I'm convinced air was getting in through there (idle changed if I covered it with my finger) so I JB welded a little piece of coolant hose I cut over it. No further code in the 1500 miles since.

However, I found the hole while fixing a leak in my valley gasket so there are some other variables in the mix.

 

Check this out
https://www.autocodes.com/p1174_land-rover.html

 

There is supposed to be a long guide/stud there. I misplaced mine years ago when I first did my head gaskets. I've since bought three parts rovers and none of them had it either. JB weld is a wonderful thing!

 

I knew there was something I forgot to mention in my post. I did the O2's as well. Had a lot of trouble with Bosch ones on AMZN, went with the Walkers which are the standard replacements in the UK. Same price as "B's" on AMZN, got them from AtlBrit.
I don't think I have that hole(D2 04) but i will look today.

 

Fuel injector O-rings