To start from the beginning, I broke a motor mount, which subsequently broke the distributor in my 94 Xj. Well this happened back on Easter weekend and I have just finally gotten around to fixing the mount and the distributor. About two miles into a test drive, my oil pressure gauge read 0 and I started noticing a tick in the motor which told me I had a genuine oil pressure problem. I immediately turned around and headed home, all the while the motor getting more "diesely" as I drove. Now I KNOW I had oil pressure when I test fired it in the driveway because I could hear the oil draining back into the pan when I shut it off. So what could cause sudden total loss of oil pressure? Can an oil pump just suddenly crap out? Maybe the check valve in the pump seized up from sitting so long?
When the motor mount broke, the motor listed to one side and rested with the distributor against the fender well which broke the "neck" of the distributor, just above where it goes into the motor. I swapped out the distributor with one out of my "parts" XJ
UPDATE: I found the culprit for the lack of oil pressure. Somehow while installing the distributor, I snapped the tab off of the base while tightening the bolt, allowing it to slide upward and losing contact with oil pump drive. DOH!!! So much for having a parts jeep, now I still need to buy a distributor.
So, my oil pressure has been reading 10 at start to 20max when I'm on the throttle (oil level is normal) and the motor has started to run really rough, sounds like an old beat up truck from the 80s or possibly diesel motor as you described...hard to describe like...duhduhduhduhduhduhduhduh (wanted to take a video but didn't have enough time). I was gonna drive it to work tonight then it did that and wouldn't stop, it did it the day before but once I got to 20mph it stopped and the motor started to run fine. Well last night when it did this it triggered the CEL and then the CEL started to flash for a few seconds then stopped so I turned around and parked it. So I'm curious if this is the same problem (Distributor). Like a newb when I bought the XJ last summer I didn't do the tune up like I should have.
So I need to change the cap/rotor/wires/plugs and then do a full synthetic oil change. I'm freaking myself out like Its gonna be a blown head or something so I'm hoping its not, but I didn't know it would throw a code..I'm gonna pull the code later today or friday to find out what it is. Sorry for high jacking I work nights and sit at a computer all night so I'll I have done is search the forums.
Would the tune up of the cap/rotor/wires/plugs and fresh oil probably cure this?