So, did anyone find a solution for this one? I've been wondering about the crank position sensor going bad as well. I think I need to buy another LR3 to help with diagnosis ;-)

 

Yes, I did finally find a solution(s). It was a long road but by trying each and every suggestion I was finally able to clear all the codes. I started out having so many codes that I didn't know where to start, essentially 7 of 8 cylinders were misfire, multiple at start, both banks were lean and I forget all the rest but those were the big issue. The LR3 had 210,000 miles on the V8 and had run with a lean code on bank 2 since it was still under warranty bc the dealership nor the local shop could ever successfully clear that code. I would take it in, they would do something that cost a lot of money and 2 weeks later, bam it was back. It never effected the driving so eventually I said screw it and just drove with it. When the misfire issues started, the performance was too bad to drive so I had to figure it out. I had replaced all ignition coils as maintenance about a year before so I was comfortable that they were good. First I ran a vacuum check, got smoke detector on ebay for not too much. This resulted in finding 2 leaks (1 big, I small on different banks) coming from the fuel injector o rings. Thought for sure this was the issue so I ordered o rings and replaced them all. Good news was I cleared 1 or 2 cylinder misfires, bad news was there were still 5-6 more. I checked and replaced crankcase pressure valve and hoses bc I read it could cause issues and since they were the original I figured what the heck, sadly this did not help at all. Then I tested the purge valve solenoid but it was fine which really got me mad because it is a pain to get that sucker back in the right position. Next the mass air flow sensor was tested but again it was fine. Rented a fuel pressure gauge and tested the fuel pump but again it was fine. Mine is an 06 so there was no schrader check valve, I ended up adding some temporary fuel line to make one for this test, but again the pressure was fine. This was getting frustrating to say the least. I ran a combustion test and all check out fine as well. I checked the EGR valve and it looked nasty and old so I replaced it. This cleared up another misfire code but still had plenty of cylinders not functioning properly. By this point I was somewhat lost but had a hunch it was a fuel delivery issue. I got a OTC pressurized injector cleaner and ran a can though the engine. This seemed to have the single best result as it cleared all but 2 misfire codes, so I was excited. Since I couldn't figure out any other possible problems, I finally relented and took it to the dealer so they could see if there was a program issue. They reprogrammed it and that cleared another misfire code leaving a single misfire code on the 2 cylinder. Here is where some confusion really comes in. In my manual, the engine firing order has the 2 cylinder as the second cylinder looking at the engine on the passenger side. So I simply returned that ignition coil under warranty, popped the other one in and thought I had it fixed. Wrong, it still showed misfire on 2. After some more research, I realized that the code reader does NOT read the same firing order. It reads the 2 as the first cylinder facing the engine on the driver side. I replaced that and done, no more codes. I have been driving it regularly for about a month now and still no codes, I even cleared that stubborn lean code that had haunted me for 150,000+ miles. I am so happy to have my car driving well again. All and all this process took about 3-4 months of working on it when I could and trying new ideas that I discovered on this and other land rover forums. Hope this helps.

 

Excellent post t4pizza... thanx!

This will no doubt help countless others down the road that are getting these codes. Amazing that it was multiple fixes... usually with these trucks, a single fix will address multiple problems.

 

WOW! AWESOME information! Sorry that you had to go through so much but you probably bought another 100k on the engine with all that! I just started throwing a couple of codes and I believe I got a bad tank of fuel that started the whole mess. I'm going to try and track down some BG (Thanks Abran!) stuff and run it through and then change coils, wires and plugs. The information you've provided helps us all immensely especially when there are so many shops that would start with stripping the thing down to the heads and rebuild from there.

 

Same fix for me. Changing a coil did the job.
I had started by chancing down the same rabbit hole as others (investigating MAF, throttle body, CPS).

 

Guys (and gals)... sorry, I didn't have my e-mail notifications so didn't realize folks were asking about this.
So, for starting the thread I will end it now at least! It ended up being two bad coil packs after all. The chances of two going at the same time? Good enough I guess. It could have been one, but taking them in and out doing the plugs might have done in the other.
What I did notice is that on both of the bad ones, the bottom rubber part disconnected and I had to fish that out of the spark plug hole. So, if ever taking one out and the bottom piece sticks to the plug, toss it and get a new one!
The odd thing was the issue going away when the truck warmed up totally. I still can't figure that one out... but if you have issues like that just grab a couple new coil packs. If in doubt, move a couple around and see if the code follows it.

 

Yeah, I found that moving the coil packs on misfiring cylinders is an important
troubleshooting step if you get multiple misfires all at once. It's also free and pretty easy.

I posted this Reduced engine performance message a while back hoping to help others. If I knew then what I know now I would have put "multiple misfires" in the title and not just in the body.

Also, I made a diagram based on the LR3 information from this Firing Order And Cylinder Numbers for Land Rover Engines video and some other resources I found online. It can be handy for those of us who aren't intimately familiar with the cylinder numbering scheme used.



I really appreciate all of the help I've gotten from the community on this forum.

-Rob