running issues
 

Ok so i know someone is going to search for my topic. Answer is I have and spent about 2 hrs reading last night. I got a check engine light yesterday code#1931... jeep had been running well. Then started to misfires every now and then. Thought maybe some bad gas bc it would go away run fine for a few days miss fire once and go away again. This was going on for about 2 weeks. After i reset the code it drove great last night and today then tonight comes along... misfires and then just dies. I try to start the jeep and hear a click and loose all power to everything no lights or flashers nothing. I pull the pos battery cable and reset everything hook it back up lights are back on. Try to start hear the click again no power again. I call a buddy and push my xj off the side of the road and wait. Reset everything and just to see what happens hook up jumper cables to his truck and mine starts right up. I run it home drives good didnt misfire till i was in my driveway. I turn off the xj and restart it just fine. Does anyone have an idea where i should even start to look for this issue. Its a 2000 xj with 4.0.

How olds battery ?

I just looked at that its 4 years and on the weaker side so its time to replace it. Would that cause it to loose all power but then disconnect and reconnect and it be fine?

Yes battery have plates inside them that thru time can become loose and contact each other causing all kinds of strange electrial problems . Also clean terminals well .

Im going to wait for morning get a new battery clean everything up and see what happens. I wonder if battery could cause the misfire as well or if the sensor was messing up bc of the battery as well. Thanks for your help though.

It very possible battery could replacing it at least eliminates it from the picture . Ya wont find many places open now to get a battery its 4am here... lol

Same im in Ohio oh well going to get some other odds and ends as well plugs fuel injector cleaner antifreeze fuel filter oil change and brakes are all on the list for tomorrow.

Today ...lol...

It's rare {in my experience} that a battery just totally craps out all at one time. I think a connection is probably the issue. Silly queston, but have you checked the grounds? Not just pullingthe treminal at the battery and cleaning it, but actually strip a new 1/2 inch of the line going into the treminal holder, and reattaching it. When I pulled of mine, I had to strip it back 3 inches to get to clean copper... it was all corroded inside the casing for the first few inches.

Second, check and clean the grounds at the body, and engine. Actually pull them off, attach a little wire wheel to your drill, and spin the heck out of these. It helps to use a pair of vice-grips or needle-nose to hold the wire heads ad screws to wire brush them clean. It save the skin and stops you from losing hold, shooting the bolt across the garage floor.

Third, check and clean the positive connections on your starter. It's where all your juice runs from your battery.


Again... you should have nice, shiny, eat-off-of clean connections. Don't waste money on a new battery. Also, if this doesn't fix it, autozone or oriely can test the battery while it's still in the jeep.

Lastly, I don't think the battery is the problem with the code flying, or the rough idling. It could be, but it also might just be two separate issues concurrently occuring.

Keep us posted, good luck, and have fun!

Ok heres an update today topped off coolent and added fuel injector cleaner to a take of midgrade. Tested the battery, alternator, and starter. All tested out good, but the battery is right on the border of being weak. The connections of the wires going into the battery terminal connectors were a little loose so made sure they were clean and tight. I only got to drive about 7 miles back home but noticed the head lights were brighter and engine seamed to run smoother but I sill need to drive more to see if the issues are gone. :)

Ok drove about 85 miles this morning and the jeep ran great had awesome power. Then while driving down the highway engine just turned off. I pit the jeep in neutral and restarted it and drove to my exit. It turned off again there. Started right back up. Decided to bring the back roads home to not get stuck on busy roads and missfired a few time. Engine light came back on(havnt ran it for the code yet). Next up pulling the sensors and testing them.

Batterys on boarder line of weak that rifght there should be a sign replace it winters coming your gonna get stranded.

Ok yesterday i changed out the cps topped off all fluids filled up with midgrade and the jeep has been running like a champ. Smooth idle and just runs great. The hardest part was figuring out how to get to the bolts. Tip for future people I used an 11mm swivel socket. On an 18" extension. Made it pretty easy but i tried a few shorter extensions with swivels in the middle it might have worked but i found what I liked. Thanks to everyone who has helped. :)