Hey guys I have a 99 WJ with a 4.7 v8 and the past few weeks it will frequently shut off while driving. It only showed one code of engine speed sensor/crank position sensor. so i replaced it and yet the problem still continued. now when it shuts off all the guages go to 0 and all the instrament lights come on. you can try and start the car over and over but it wont actually start until it seems to either cool off or the system recycles itself. im not too sure what else to try. i have replaced the crank position sensor, cam position sensor, fuel filter, coolant temp sensor and checked the fuel pressure which is normal. this continues to be a puzzling problem especially since there is no check engine light that comes on when it shuts off which leaves me scratching my head. any help with any other possible reasons would be greatly appreciated.
also when you replace any sensor you have to rest the computer.... disconnect neg cable. put foot on brake, and keep key turned all the way for 30 seconds
What's the idea with holding the brake and turning the key? To discharge any capacitors faster or just good luck folklore?
BTW, back in the day my dad had an '87 Aerostar that did this. Pretty sure it turned out to be a bad gascap not letting air into the tank. Once removed, the van ran fine. I highly doubt your solution would be this easy, but you seem to have tried everything else.
So I installed the flux capacitor but the Jeep just won't do 88 mph.
I'm having the exact same symptoms as you describe. My CPS arrives today by way of UPS. I hope I don't have to chase this gremlin till my wallet weeps. So many horror stories related to this issue.
So far I've replaced fuel filter, Dist cap & rotor, Plugs & wires, and disabled the factory security system to no avail.
It's so random that there is no pattern as to when and where it shuts off. Doing 60mph, stopped, letting it warm up in the driveway... anytime, anyplace. Weird part is, I usually just pull right over when the engine stalls, but this last time, I put my foot in the gas when it stalled, and like a switch, the engine came back on and drove just fine. Sadly this Jeep has been reduced to just picking my daughter up from school like 4.5 miles away, but now it's even doing it once or trice in just that small trip.
I'm not getting any codes other than code 12 (battery has been disconnected recently) which is true.
Battery may also be the culprit here. It will barely idle with a bad battery and if the battery is disconnected when it is running due to a bad cable or terminal, it will cause a shut down. If there's a bad cell in that battery, it can cause this and possible an intermittent issue.
Try one from another vehicle first to test or just replace it before you throw more parts at it.
2000 Laredo 4.7L Selec-Trac. 177K miles, Leather, 245 tires, tow package, crappy CD changer, full size spare, roof cross-rails & sunroof. Changes & fixes: Rear Addco sway bar & greasble bushings, upgraded headlights, upgraded tail lights, new hood struts (replaced 2X), new rear hatchglass struts, new radiator (replaced 3X), new oil pressure sending unit (replaced 4X), 2 new speed sensors, 2 new door lock actuators, new ignition key cylinder, chrome front tow hooks, Mobil 1 Synthetic 5/30, Purolator Pure One oil filter, EBC slotted & dimpled rotors, EBC Greenstuff pads, new front shocks (replaced 3X), new rear shocks (replaced 2X), new IRO steering stabilizer, new timing chain cover, new water pump, thermostat, new thermostat housing, new high pressure power steering hose, Michelin-X radials, new sunroof assembly, new single-piece lug nuts, new exhaust manifold studs & gasket on driver's side, new Durango alternator. Jeepforum.com sticker, Visit cobaltboatsforum.com when you can!