I have a 2015 XF 3.0 Supercharged. Could someone tell me, when standing at the front of the car looking towards the rear, which is MAF A (1) and which is MAF B? (2). My workshop manual has some conflicting information which is confusing things a bit.

I've also searched the manual for some specs regarding MAF airflow in g/s at idle, but am coming up short there as well. Anyone know the specs for the 3.0 SC? The reason I'm asking is I'm troubleshooting some higher than normal LTFT's (+10 in both banks).

Thanks in advance!

 

Does this help you, should be similar on XJ: https://www.jaguarforums.com/forum/x...solved-217882/

you could have a vacuum leak. I would check the air intake plastic under the hose clamp that connects the air intake to the throttle body. Mine was cracked (again on an XJ). Then check if your throttle body butterfly valve is clean.

Best of luck!

 

If you have a code reader, you could unplug one and the code generated would tell you if the one unplugged was A or B

 

Thanks, your link confirmed what I was thinking. I have already replaced the intake tube. As you mentioned, mine was cracked and deteriorated at the connection to the throttle body. Because the fuel trims are identical in both banks (+8 this morning) my hunch is there is a slight leak somewhere in the intake track before the throttle body. My MAF readings this morning at idle and warm were MAF A - 1.8 g/s and MAF B - 1.59 g/s. These are probably within spec but I'm not sure what the target g/s is at idle for the 3.0SC.

 

You could have an intake leak anywhere from air mass to intake manifold. I would check complete intake track all the way to the manifold. I have seen numerous leaks at PCV valve.

 

The PCV was my next point of interest. I actually purchased a new PCV valve several months back but haven't installed it. I've heard the diaphragm in the PCV valve can rip which can cause a leak. I noticed when I pulled the hose off the throttle body there was some oil (blow by) in the TB orifice as well. Can the PCV valve be replaced without dismantling the entire car? I noticed there are some hoses that go over the top of it. I assume, with some patience, I could pop the PCV out without removing everything.