Just picked up a 2001 XJR with just under 75k on it.

Problem:
When I stab the throttle it bogs down until it reaches just over 3000rpm then takes off at a good clip.
Other things I noticed too. When in parkand in sport mode(and the throttle is floored) it also bogs down until reaching the 3000rpm limiter. In non-sport mode and in park(and the throttle is floored) the bogging is much less noticable but still there.

I haven't done much yet other than pulling the MAF sensor and gave it a cleaning with some MAF cleaner solvent. The actual tip of the sensor wire has a redish amber match-head sized bulb on the end of it (is that normal) and the side facing the air cleaner was black while the other side I could see filiment (or whatever its called) through the match-head sized translucent casing. The MAF solent cleaned it up so both sides where translucent. I am not sure what it is supose to look like in new condition. I could post a pic if it seems unclear in my description. The air filter also apears a bit dingy and I took it out and blew out most of the crap I could to clean it up somewhat.

Anyhow, it made no improvement. On order I have a K&N filter (dont expect it to fix anything but a new filter was in order) and also a basic OBDII scanner to see if I can find anything.

I read somewhere about checking the ERG valve for buildup? I got a picture of what it looks like but I am unable to locate it. Mind you my garage is dark and I seem to work everyday until it is dark out.

Any help or direction on what to look for would be greatly appreciated.

 

Well, I took out the MAF sensor again (in the daylight this time) and saw that what I needed to be cleaning I wasn't. So a few more squirts of MAF solvent and a bunch of black liquid come rolling out. After things dried out and reinstalled my low rpm boggin is gone. Now I still think the rear tires should go up in smoke when I stab it without needing to brake torqe it but it is much much better than before. Hopefully the OBDII reader I ordered will tell me some more. I appreciate the quick fast response. Thanks much. Will keep you all informed on my findings.

Also, on the MAF sensor, what is that other sensor that has the glass bead on the end of it and what does it do?