2011 Land Rover LR four and on both banks, at idle, the fuel trims are at 30. If I bring the RPMs up to around 3000 the fuel trims come back down into the 1 to 3% range and it looks like everything is adjusting as normal. At idle it’s definitely rough and feels like a little bit lumpy. There are no pending codes. I did a smoke test and found a little bit of smoke coming out of the front right driver’s corner under the valve cover. Is this my most likely culprit? The map sensor numbers seemed a little bit low. at idle I was around .3bar but I don’t have a good understanding of what exactly that means and if it could be related to a leaking valve cover gasket. I did spray some carburetor cleaner at the corner where I found the leak and there was no reaction from the engine and I also sprayed some carburetor cleaner on the PCV valves and had no reaction. I did find it unusual that one of the mass airflow sensors was reading -30 V while the other mouse airflow sensor was reading the wound 1.2 V

What would you do first?

 

-30v??

 

yes. Pictures uploaded. Switched mafs to opposite sides and -30 did not follow. Stayed on same side.
do I test reference voltage now?

 

Hoping somebody will give me some about this field trim being so high being directly related to the leak in the valve cover. I wouldn’t say it’s a huge leak, but the smoke definitely couldn’t be seen coming out the corner. I did spray carburetor cleaner all over that particular spot and no uptick RPM and I also use the same carb cleaner on the PCv valves and no change in the RPM