All,
I have an issue with my 07 4.4 LR3 throwing the Lean Codes. I have replaced the EGR & Mass Air Flow sensor and it still returns. My mechanic said that it needs a software update from Big Land Rover, but I am not so sure, given that it is an 07. These issues have not effected my fuel economy or caused a rough idle. It has been occurring since March. Unfortunately, here in Northern Virginia I need these to be resolved to continue my registration. I have cleared the adaptation settings with the GAP tool etc. but no dice. I am really at a loss.
I have reviewed many of the posting about this code and it seems like there is no once solution.
So I am looking for any advice.
Thanks,
James

 

Lean of course means an excess of air and a shortage of fuel. I would first try some fuel treatment. Seafoam is my preferred snake oil as its proven to work super well. I tend to use more than directed in the fuel tank. B12 is another great option. For the air side, you need to remove the intake tubes and inspect then very closely, mainly downstream of the MAF sensor. A small hole is like a hole in a driving straw. Can have a pretty big impact. You also may want to replace the PCV. On the 4.4 its on the passenger side, looks like a black hockey puck but flatter. Two screws, one pinch-style-to-remove hose connection. Stupid easy to replace. Also look at the oil dip tube o-ring at the end and the oil filler neck. The smallest air leak can cause issues. Oh and speaking of EGR, the far back end behind the engine can come lose. I think two 10 or 8mm bolts. When it does you can also get an erroneous pick up of fresh air.

Thread on intake cracks:
https://landroverforums.com/forum/lr...sonator-91604/

 

Thank you!
I replaced the PCV so its not that- I will look for additional leaks in areas you mentioned.
Quick follow-up- could it be a failed software update? Reference number LA303-007 sections 303-14?
Thats what my mechanic was saying.
Regardless, I will look for these leaks in the areas mentioned.
:-)

 

I dont see how you could have a failed software update if the mechanic did not do any updates. So no, I dont see how it could be software.

 

Following up on Lean codes-
I tried to locate a possible leak with Carb Cleaner and listening for change in idle and that did not work.
I also took it in to a shop and they tried to locate any leaks, and nothing was found.
My O2 sensors were original, so I have replaced both sets, up and down stream sensors. Fun fact, everything was rusted so the labor costs were exceedingly high! As I was driving it, the codes returned.
I just don't understand what is happening. the Long term fuel trim is running 23% on both.
Thanks,
James

 

2. questions.

1. What are the SHORT term fuel trends? Remember in the end we want them near 0% when added together and no more that 10% between the long and short term numbers.
2. Have you done an adaptation reset?

PK three..... Did you find any holes in the intake tubing? It is most likely the issue despite numerous inspections.

Let us know what you find.

Jeff

 

Yes, I was chasing lean codes for awhile, and it eventually turned out to be a weak injector or two. Many others have had them from intake leaks. You really want to do a smoke test to clearly diagnose those. The areas Dakota mentioned are the usual suspects.

 

So I had it smoke tested and there appears to be a small leak on the o rings for the EGR valve.
The shop indicated the the MAP sensor seemed to be erratic which also could be causing the issue.
I had the injectors cleaned, they said everything seemed to flow fine.
For the Two questions
1. Short term (over 1minute of various rpms) fuel trim2 Yes the adaptations have been reset, as well as a hard reset using the battery disconnect.

I ordered a new MAP sensor, and they have some new O rings for the EGR.

Thank you!

 

The the smoke test determine the week injector?

 

Smoke test is for finding air leaks, it won’t diagnose an issue with fuel delivery.

Some vehicles can diagnose injector problems with the computer, but with the LR3 the only way I know of is to pull them and bench test. You can check electric resistance on the injectors while in car, but this only checks the solenoid health. Usually what causes injector problems are clogs or bad seals. They end up not delivering enough fuel or poorly atomize (mist) it. You’ll only confirm this with a bench test, which it sounds like has been done.

Sounds like you are still chasing this problem. What else have you done since the last update?