Loss of power, intake poping, oh my
'96 4.0 aw4 np231
Last weekend while out wheeling I got hung up on the muffler. Ended up coming loose and hanging from the o2 wires. Got that fixed and on the way home it threw a CEL for the rear o2. Figured one of the wires ripped out. Replaced the o2 and got the exhaust welded back up and now I have popping coming from the intake and imtermintent loss of power.
Loss of power only happens at part throttle. At WOT it runs fine. When cruising off throttle it feels like it wants to stall but never will. If I take it out of gear it will idle and rev up with no issue.
Fuel pressure while running is 49psi. Plugs are tan in color. No vacuum leaks. Both o2 sensors are new. Just put a new cat in as well. Checked the fuse's as well.
What am I missing? Any ideas?
Edit: Read some more. TPS and Up Stream o2 seem to be the common issue. Will have to check those tomorrow, its dark now.
Last weekend while out wheeling I got hung up on the muffler. Ended up coming loose and hanging from the o2 wires. Got that fixed and on the way home it threw a CEL for the rear o2. Figured one of the wires ripped out. Replaced the o2 and got the exhaust welded back up and now I have popping coming from the intake and imtermintent loss of power.
Loss of power only happens at part throttle. At WOT it runs fine. When cruising off throttle it feels like it wants to stall but never will. If I take it out of gear it will idle and rev up with no issue.
Fuel pressure while running is 49psi. Plugs are tan in color. No vacuum leaks. Both o2 sensors are new. Just put a new cat in as well. Checked the fuse's as well.
What am I missing? Any ideas?

Edit: Read some more. TPS and Up Stream o2 seem to be the common issue. Will have to check those tomorrow, its dark now.
Last edited by UserID6095; Oct 30, 2010 at 06:36 PM.
It gave me P0138. Front o2, heated.
I have a brand new Bosch o2 in there and it still throws the CEL. From reading around the web, others had a similar lean mixture (throttle hesitation) after swapping to a Bosch o2. They recommended a MOPAR o2 only. So come morning Im going to unplug the upstream o2 and drive it around. If the lean issue stops then I will know its bad and will be replaced with a MOPAR unit.
Other culprit may be TPS. I will have to find procedure for testing it.
I have a brand new Bosch o2 in there and it still throws the CEL. From reading around the web, others had a similar lean mixture (throttle hesitation) after swapping to a Bosch o2. They recommended a MOPAR o2 only. So come morning Im going to unplug the upstream o2 and drive it around. If the lean issue stops then I will know its bad and will be replaced with a MOPAR unit.
Other culprit may be TPS. I will have to find procedure for testing it.
I checked all the fuse's in the Power Distribution Center. I pulled each one out, checked, cleaned and then put back in.
Do you happen to know which one exactly I should be looking at?
Do you happen to know which one exactly I should be looking at?
Last edited by UserID6095; Oct 30, 2010 at 09:00 PM.
Probably why I couldnt find it in the PDC. haha
Thanks, I will check that as well.
Passenger side or drivers side? I didnt see a fuse panel on the passenger side.
Thanks, I will check that as well.
Passenger side or drivers side? I didnt see a fuse panel on the passenger side.
Last edited by UserID6095; Oct 30, 2010 at 09:29 PM.
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