Hey, I know this is just a Jeep problem and not the anguished cry of a sick mind(or 3), but if I don't get it fixed, it might turn into one. :-(
'94 YJ, 4.0/5sp
Just started last weekend. After driving 40 or 50 miles all of a sudden engine refuses to rev above about 1500-2000rpm without cutting out. Idles fine, restarts no problem, and if you're in downtown traffic you never know there's a problem. Just running out on the open road. Last night it started acting up on our way to a concert, didn't have time to mess with it, so called one of my kids who lives on our route and switched out cars. Later on, when I picked the Jeep back up(4 hours later, maybe)it ran fine most of the way home...until it hit about 45 miles from startup. No check engine light, plugs/wires/cap/rotor/air and fuel filters changed about 2 months ago(maintenance, not chasing any problems at that time). I changed the fuel filter again last weekend when this cropped up, because it sorta felt like low fuel pressure. Went out this morning and cleaned/inspected connectors for the crank sensor, cam sensor, IAC, and TPS. Haven't driven it the required mileage yet, so I won't know if it's fixed yet, but was fishing for any ideas I might have missed. I'm thinking maybe fuel pump(maybe 3-4 years old), or coil(OEM, I'm sure). Don't have my fuel pressure gauge at home, but I'm planning in checking that probably Monday night. Coil ohmed out good this morning, but then again it's not acting up right now.
-- Old Crow '82 FLTC(P) 'Mistress Pearl' '87 FLTC 'Crosseyed Mary' '61 F-100 BS#133, SENS, TOMKAT, SLOB#13, MAMBM