Result!
I'm really happy for this outcome.

 

Fingers crossed for you mate! Feels good when you get something fixed yourself eh!?

 

I love a happy ending!

That bent plenum gasket was probably an issue. I am really glad your truck is behaving.

In my threads you will note that when something goes wrong I used to panic, then throw parts at it, always assuming that the rest of my former parts were good and all of my work was good. It is almost always something simple. Good job.

 

So the misfire trouble codes have returned - kinda. Seems each day when I start the truck for the first time they come on within first 5 minutes of operation. I clear them and they dont come back for the rest of the day, even when I turn off the engine and let the truck sit for afew hours. Yesterday for example I started the truck and the codes: P0300, P0301, P0306, P0305 and P0307 popped up. Cleared them and dove down to South Deerfield Massachusetts and back again with no issues, no codes, no rough operation or flashing CEL. Roughly 68 mile trip one way so figure 138 miles plus we stopped at afew scenic places along the way and got lunch. Not sure what to make of this.

Another new issue Im having is the key hole. All the sudden my key does not seem to want to fit all the way into the keyhole slot in the door handle, thus cant lock/unlock the truck. Have to keep playing with it and kinda wiggle the key around until it slides in the rest of the way. Its a brand new genuine door handle assembly. Came with a new spare key and I tried using the spare and still same issue so I know its not an issue with the key being bent or damaged. Any thoughts? FYI the key fob stopped working immediately after my mechanic let the truck battery die. Truck was locked while the battery drained so even after he managed to get the hood open and the battery charged back up he was unable to get into the truck because of the alarm. He had to smash the door handle assembly to get access to the truck. $$$ out of my pocket for a new door handle assembly and Land Rover dealer had to program it to my VIN. Ever since the key fob has not worked though it still lights up when you press the button. Has new battery in remote to. So not sure why after 3 months Im having issues with the door handle assembly.

 

Does it run rough on the first startup of the day? I hate to ask but have you lost any coolant at all? Surely you don't have a head gasket issue. Surely. But misfires in the morning then smooth sailing the rest of the day is a possibility. As is the injectors being slightly clogged and spraying better when they warm up.

I bet one of your pins isn't happy in the door handle. You've had more problems than anyone but me! The best you can do is to put dry graphite on your key and slide it in and out.

I don't know why the fob wouldn't work. Mine doesn't work either but I know why mine doesn't. If the mechanic has a nanocom or equivalent he can program the system to accept the fob's code.

 

Can also stick open and dump fuel until rail pressure drops.
......

 

Whoa, don't I know it. And hydrolock a cylinder, bending the rod and destroying the piston and oil pump. Been there, done that.

 

Are these actual codes, or Pending codes? After you clear the codes are you monitoring the systems?

 

I somehow missed the number of misfires and the general misfire. Apparently I can't read. Triarii that's bizarre. I would almost swear it is a MAF or big vacuum leak that is causing you grief.

Do you have a spare MAF or access to one for thirty minutes?

 

Charlie_V:
Truck seems to runs fine upon start up, and even after warmed up. I'm not having any acceleration issues like I was before either. Before I did some tinkering I noted how the truck ran rough, flashing check engine light constantly on and there was noticeable hesitation while accelerating to higher speeds. Have not had any of those symptoms since I tinkered with ****. I have not noticed any coolant lose and if you look at all the pictures above the top of the block is clean with no visible coolant, oil or fuel leaks. The coolant in the expansion tank remains at the full line and engine temps have been normal with no spikes. I do not have a spare MAF sensor and per everyones advice opted not to buy random parts unless I need them... I spoke to my mechanic about the possibility of a massive vacuum leak and he said I would hear it if that was the case. Plus I would be getting vacuum leak related fault codes.

fishEH:
The codes are fault codes, not pending codes and once I clear them, often times they wont reappear but sometimes Ultra Gauge will alert me of new pending codes later on in the day but the CEL does not reappear.