Thanks for getting back so quickly and for putting me right, the OBD2 scanner can read fuel pressure. Regardless of rpm or load, it's holding at 46psi +/- 1psi.

Not sure if that's where it should be, or way off.

Cheers.

 

The 101 code on my 04 XJ8 was those 8 hidden, rubber intake manifold rubber gaskets.
Not that hard a job if you take your time, and follow the instructions, with all the pictures.
You just may get to know where some things are located, how to disconnect and remove, that you may have not have dealt with before.

 

Thanks Wingrider, appreciate the help. I'll see if changing the MAF sensor makes it go away. If not, I'll definitely take a look.

 

Wish you luck, you just may be luckier than me.
I hate to be the bearer of bad news,

 

45 psi is too low-should be 55 psi for NA v8

 

Thanks Meirion. Would that also be the same for the supercharged? That's what mine is, not the NA.

Thanks.

 

I just wanted to add that I did replace the fuel filter today. In park, at idle or 2500rpm, the fuel pressure is still 46psi, however, under driving loads, it goes up to the mid 60s. Don't know if that makes any difference. Just wanted give you some more data.

Thanks

 

To everyone who's helped me with this problem, I want to say a big thank you and let you know I finally fixed it. It was the MAF sensor that triggered the O2 sensor codes. Having tried pretty much everything else, I finally changed the MAF sensor yesterday, reset the codes and have had 10 clear drive cycles with no recurrence. The only thing I got was a P0101 on the 10th cycle, but that's probably as a result of the calibration to the new MAF. I cleared that, so letslhope they all stay away and after more than a year, this is finally the end of it.

Thanks again!!

 

Easy fixes that don't cost a lot are the best kind.
Glad to hear your issues are resolved.