Solomon7

Looks like this guy had th esame prob with pretty much the same rig, but he never posted back with the outcome/diagnosis/fix.
http://www.naxja.org/forum/showthread.php?t=13756

Mine like his is a 96, 4.0, AW4, NP231,and 151,000 on the clock.

I got 2 43s with the on off on off on OBD.
It's had rough hot restarts for a while but I've been told that's typical, but till noe it's never thrown a code, much less 2 of the same.
Any ideas? I'm thinking 1.coil 2.MAP or 3. injectors (please no...they's pricey lol)
Don't have a multimeter to test so short of taking it to the shop($$$) what can I do to diagnose or fix?

Solomon7

Got it sorted out and it runs great again....except that annoying #5 or 6 lifter that takes 15-20 secs to pump up; typical

I changed plugs, wires, cap and rotor (they were fine with 50k on them).
All the old E3 plugs lookes nice till I realized I never gapped them. .085!
Think that may have been where my mileage went. Back up to 18-20 now!

Changed tranny fluid. Looked great allbeit a little overfilled. Not anymore.

Cleaned the throttle body since it's been about 20k since the MCCC.
Just a tiny carbon ring near the plate causing it to stick slightly when released.
Smooth now and shiny inside. Cleaned up the IACV.

Took it out a few times and same problems. Even unplugged the TCU and test drove. Tranny is golden.

I've been meaning to replace the TPS anyways. Bought a Borg Warner from Shucks/O'reilly's for 34.99
Total crap. Idle was at 11-1200 and wouldn't drop w/o a jiggle and firm upward pull on the linkage to the plate. THought maybe worn linkage but the wife reminded me with the old XJ I returned 2 or 3 TPSs before getting the OEM one. She rememberd cuz I *****ed all night about how taxed it was lol!

Went to the stealership and got a factory replacement for 83 bucks, yay.
Plugged it in, started her up.
Smooth 2 chug start, theusual tick and in 5 secs,
Beautiful! Right at +/-800 rpms with a nice banks header knockoff warble again.
Took to the mech, Stuck the old TPS back in and he scoped it. Turns out the TPS was fluttering/surgin/cutting out randomly at certain points in the throttle causing the trans to become confused. Took him a while to get it to freak out but when it did it was all over the place. The new one read perfectly.

The rpms even drop right away now when I let off on the highway. No more tapping the brake pedal to disengage! No more hot start issues either.

Looks like I solved most of my probs! Now just gotta do the RMS, oil filter adapter and valve cover (I see some grime growing here and there, slooooow seep) and it's on to the fun stuff. Sliders, bumpers, skids etc.
Oh yeah and finding someone to help me fit this Landy Disco 8.8 in to the XJ....somehow. Man, I wish I had space and a welder something more than just an axle and an idea.. Good opportunity to make some new firends I guess!

JeepingDan

What also helps. Get from the dealer a can of carbon cleaner. How I do this. I empty the entire can into the throttle body while idling and shut it of when can is empty. Let it sit over night so the stuff gets a chance to soak into the intake and exaust valves. Next day fire it up and take it for a good burn. It's will smoke for a few minutes but thats just the junk in the cylinders burning up. I do this once a year and everytime I notice a differents