My local shop that always helps me out has called in a favor from me. I am trying to help troubleshoot 2001 XJR that is running rich.

I am starting at the MAF which is giving some weird readings. I cannot make out the part numbers and revision letters on the end. None of it seems to make sense to me.

Car currently has LNE1620 CB
My '01 SVP has a BA
Looks like this is for a N/A engine

Dealership told me it needs BA
Heritage online says BB

I'm assuming the first letter is a different type of MAF and the second letter is a revision part number?

Could there be that big of difference between the NA and SC MAFs it that is it?

Fuel trims are averaging in last run around -10% Bank2 downstream acting erratic also but since I found the part number issue I'm starting here.

Any help on the Jaguar Revision coding in general would be helpful.
Any help on this car specific is also helpful.
Also, any ideas where to get the 1620BAor BB for less than $230?

 

My 2000 has BB that I just replaced (the whole assembly) about a year ago and its an R model. I looked around and almost every one listed as CB was on a N/A XK8, but also showed XJ8's. The other reference was a CA.
You'll have to tell us, but supposedly you can just replace the Flow Meter (197408-0010 Air Flow Meter) and it runs about $45.
When I use one of my favorite search sites... http://frugalmechanic.com/ ....it asks for 4.0L S/C MPI or 4.0L S/C SFI MFI B, only you can answer that I think.
What I like about that site is it almost always has multiple reference part numbers.

 

Not answering your question, but something you might want to check before you order a new MAF sensor, it saved me almost 200 bucks (post 22).
https://www.jaguarforums.com/forum/x...2/#post1500877
I had the same weird readings (which went all wrong over a distance of some 50 miles).

Since this posting I have done some more miles, and the LTFT creeped further back to around -3 at idle.

 

Haha, yes I saw that and tried it last week. Read that thread about a dozen times to see if I missed anything. I have not yet tried to probe from the back but may try in next couple of days.

To add to the confusion I have a 1620CA MAF for sale in classifieds and tried that one. Set off light after quick drive.

Other than poor mpg, very slight rough idle and O2 lagging the car is fine, no check engine light or anything. Owner just knows there is something up and wants it fixed.

These guys help me a ton and now shoe is on other foot.......ill start trying everything.

 

Well, if the CA is a N/A application, then the BB must be your answer on the XJR.