Just bought my 2003 XJ8 Vanden Plas, and now have a couple of codes pop up P0172 and P0175 with the "Restricted Performance" did some checking and figure it is cheaper and best to start with a air filter change and cleaning the MAF. I know it is recommended to use MAF cleaner, but would it hurt to use electronic cleaner spray? or is it different from the MAF cleaner spray. As soon as we get a break again from this heat out here in the middle of the country, I also plan on doing my usual stuff when buying a used car, change filters, oil and plugs, check and clean connectors, and before winter, new tires and have transmissions serviced (even tho they say it doesn't need)

 

It has been said over and over again on this forum, but before you do anything else, first be sure your battery is in good condition, and fully loaded.
These cars do strange things if the battery is not up to par.
Then, do a hard reset and check for codes again, go from there ...

 

To answer your original question. Absolutely DO NOT use anything but MAF cleaner on the MAF and throttle body. Anything else can damage the MAF and damage the coatings in the throttle body.
It sounds as though you are on the right track for starting out with the new CAT. Good luck and we are all willing to help if you need us.

 

Clean the MAF with MAF cleaner; throttle bore with throttle cleaner.

Every time I have had this issue on any of the Jag V8s I have owned, it proved to be dirty injectors -- but there are many threads with many issues identified. BG44 or SeaFoam (a good cleaner) is a place to start after you have cleaned the MAF and throttle bore and assured you have a clean air filter.

 

After I got back from the parts store, opened the hood to let the motor cool done for a bit (been hot this way in Nebraska with heat index 110), anyhow, removed and cleaned the MAF, had to clean out the airfilter box, had some amount of dirt and debris, put it together, cleared the codes and so far all is good. Something else I noticed when I went to unclip the latches on the box, and am sure it had to do with the codes, someone before I bought the car did not have the 2 front latches on properly oh and did put in a new filter.