98 Jeep Wrangler Sputtering

[98TJay]

Hey Guys - I need some help. My 98 Wrangler 4.0L 6 cylander is sputtering jumping and almost stalling. I just replaced the alternator but it is still sputtering and losing power and then jumping forward. I though it was fixed after I replaced the alternator and now it is back. Also - when it starts to sputter my dash lights go dim and my heater starts to turn off. Any idea on the possible problem? Any ideas on the fix? I think I might give it a tune up this weekend.

I read something about the O2 Sensor maybe being the issue? Any other ideas. Thanks.

[ollllllo]

if your dash light are dimming i wouldnt think its related to an o2 sensor.
Im no mechanic, but you can start with the basics...

check the alternator connections( clean them and re tighten)
Check battery terminals ( remove,clean and tighten)
Does 98 have distibutor? if so remove cap and look for broken or worn contacts
check all plug wires for a shorts or arching.

to me it sounds electrical/ ground,  but im sure some of the other guys can add their input.

no check engine light?
good luck keep us updated

[MrMindless]

battery connection sounds like it to me.  if not I\'d be looking for bad grounds.

[ollllllo]

if you you need a terminal cleaner... I know someone who has a nice one he might loan you. ;)

[Crusarius]

if its sputtering causing low idle condition more than likely that would be the reason the lights are dimming.

you getting a check engine light at all?

tuneup could remedy this issue.

kinda sounds like it is searching for idle. you just had the battery disconnected. it does take a bit for the 4.0 to relearn.

[98TJay]

When I first posted here the Check Engine light was not on - since then it has come on. I am going to Auto Zone after work to use the computer. I will post the errors that I am getting later.

I am just not sure where to go from here - I could probably give it a tune up but some research I am doing on line it sounds like Throttle Body Sensor or something? Maybe the Fuel Pump? Just not too sure. I might replace the battery and check the cables.

It is going to be a long weekend.

[98TJay]

Ok guys - the computer is showing PO133, PO135, and PO463. I looked them up and this is what I got:

P0133 (M) 1/1 O2 Sensor Slow Response Oxygen sensor response slower than minimum required switching frequency.

P0135 (M) 1/1 O2 Sensor Heater Failure Oxygen sensor heater element malfunction.

P0463 (M) Fuel Level Sending Unit Volts Too High Circuit shorted to voltage between PCM and fuel gauge sending unit.

How difficult is it to fix the O2 Sensor? I think I read something about unhooking it to check? What will it cost? Will this fix the whole problem? Thanks guys.

[jeepfd16]

Replase the o2 and the prob should go away its not to bad to do.

[Scooter]

I had this problem with my \'97. The only thing is that I can\'t remember which one of the fixes I did took care of the problem. Here\'s the list... Check the passenger side wiring harness at the bottom of the firewall and look for a sizable ground wire, I had one that had corroded through and was causing issues. Also, I had to replace the idle position sensor? I think. It\'s been a couple years but I think it\'s the goldish colored unit that is connected to the throttle body. I\'m almost positive that was what took care of the problem.

[dgray69]

I agree with scooter, had same problem, same fix with 01 expedition

[98TJay]

Hey guys - I gave the Jeep a tune up. I replaced the plugs and cleaned up the battery terminals and replaced the battery. The Jeep seems to be running good now but the CE light is still on. I am going to replace the O2 sensor as soon as I get the time. Seems to good to be true though. I hope it continues to run like it has - could it have been that when I replaced the alternator - because the battery was bad the alternator needed to charge? Thanks.

[dgray69]

you say your ce light is still on? disconect battery for a minute, hook back up, that should clear the computer, if not its 02 censor, then disconect battery, it will reset

[98TJay]

I disconnected the battery and the CE keeps going on and off. I havent replaced the O2 Sensor yet. It was running ok for about a week but now the sputtering is back. It wil sputter and jump for about 5 minutes of driving then it goes away. Still a little puzzled. I am going to replace the O2 this weekend. Maybe something with the throttle body? Thanks.

[gCracker]

definitely sounds like O2 sensor.. My TJ did that when I bought it.. replaced the sensor and it has been happy since.. but now the wife\'s ZJ is starting to do it..

[itjustmeD]

I\'m far from an expert but have you checked your fuse-able links? It sounds like you\'ve got something that is causing high resistance, consequently low current.