1992 Cherokee Sport, 4.0L, Auto, Part Time 4x4
Started having trouble with stalling a couple years ago. Has been parked for a while (I bought a '99 Cherokee in the meantime), and I'm hoping to have time over Christmas to work on it to get it running to the point where I can sell it.
Basically, it stalls out when driving. Seems like it does it when it's warm or cold, day or night, no real pattern to when it happens. I've replaced the CPS three times, no luck. I've replaced the fuel pump, plugs, wires, cap, rotor, and coil. I've checked for bad grounds and can't find any. I don't get any engine codes either.
The stalling (as best I can tell) seems to be electrical in nature (from what I remember, I can hear the fuel pump running even when it won't start, so I'm thinking it's spark). When the jeep does decide to run, runs well, and will go for days without a hint of a problem, then might decide to stall several times in one day. Sometimes it'll fire right back up, sometimes you need to wait a day. My favorite part is that every time I take it to the dealer, they can't get it to stall, and then can't diagnose the problem.
So, I'm looking for a way to test what's wrong (ie: put a multimeter across two terminals to check for voltage, or test light in a certain spot), or ideas of what to replace next. Is there a wire/pin on the ECU that goes to the coil that I can probe to see if the ECU is even trying to fire the sparkplug? I've heard something about a rollover safety switch that might go bad, or a distributor sensor that might be out (but I've also heard that the distributor sensor won't kill it once it's started??)
Do I need to consider a new ECU/ECM? If so, I'd like to pick one up at a junkyard; what other cherokee's are compatible with mine? Obviously 4.0:, but does transmission or transfer case make a difference? Power options? Sport vs. Limited??
Thanks for the help,
Wes
Started having trouble with stalling a couple years ago. Has been parked for a while (I bought a '99 Cherokee in the meantime), and I'm hoping to have time over Christmas to work on it to get it running to the point where I can sell it.
Basically, it stalls out when driving. Seems like it does it when it's warm or cold, day or night, no real pattern to when it happens. I've replaced the CPS three times, no luck. I've replaced the fuel pump, plugs, wires, cap, rotor, and coil. I've checked for bad grounds and can't find any. I don't get any engine codes either.
The stalling (as best I can tell) seems to be electrical in nature (from what I remember, I can hear the fuel pump running even when it won't start, so I'm thinking it's spark). When the jeep does decide to run, runs well, and will go for days without a hint of a problem, then might decide to stall several times in one day. Sometimes it'll fire right back up, sometimes you need to wait a day. My favorite part is that every time I take it to the dealer, they can't get it to stall, and then can't diagnose the problem.
So, I'm looking for a way to test what's wrong (ie: put a multimeter across two terminals to check for voltage, or test light in a certain spot), or ideas of what to replace next. Is there a wire/pin on the ECU that goes to the coil that I can probe to see if the ECU is even trying to fire the sparkplug? I've heard something about a rollover safety switch that might go bad, or a distributor sensor that might be out (but I've also heard that the distributor sensor won't kill it once it's started??)
Do I need to consider a new ECU/ECM? If so, I'd like to pick one up at a junkyard; what other cherokee's are compatible with mine? Obviously 4.0:, but does transmission or transfer case make a difference? Power options? Sport vs. Limited??
Thanks for the help,
Wes
