Jeep Stuttering / Stalling

RJVanna

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Original poster
Joined
Jan 13, 2025
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Location
Arkansas
Hello, I own a 2003 Jeep Wrangler X. It's a 4.0L with a automatic transmission. It's all stock so no crazy mods to worry about here.
The issue I am having is a random stuttering and almost stall on the engine. I will be driving around and the engine starts to hiccup and it looses power. I'm basically reduced to about 10mph. I rarely get any engine codes but the one I've gotten twice now is the p0174. I am aware of the confirmed code in the attached photo and I replaced the bank 2 emissions sensor. I believe that is related to the cats going out. Maybe the 2 codes are related?

Anyways back to the issue at hand, I previously thought it was bad gas so I used heet and got new gas, I also just had the fuel pump replaced, I also bought new emissions sensors. I used seafoam spray to clean the throttle body on top of the engine. I'm not sure where the issue is coming from but it's purely annoying.
I'm thinking about getting new fuel sensors. Anyone got any good ideas on what the culprit could be?

(edited)
I just got rid of the exaust code p0432, but now i have a cylinder 3 misfire code with the code p0303. in total i have both codes p0303 and p0174. The car still feels very underpowered and idles low at random.

Screenshot_20250113-131554_inCarDoc.jpg
 
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What are your O2 voltages ranging at? What percentages are your fuel trims?

Coil maybe?

Screwdriver to the injectors and listen for ticking?

-Mac
 
How many miles on it ? Have you looked at your spark plugs?

Yes, sorry I forgot to include that I changed out my plugs about 10k miles ago. The interesting thing is that the car drives fine and then it all goes down hill and stutters all of the sudden. I have to pull over turn the car off and on again to get the issue to go away. I also noticed while driving the transmission shifts at odd intervals than I am used to. This seemed like a vacuum issue even though I checked the lines for poor connections already.
 
What are your O2 voltages ranging at? What percentages are your fuel trims?

Coil maybe?

Screwdriver to the injectors and listen for ticking?

-Mac

See I thought it would be the coil but tbh it happens randomly. I can drive fine for 30 minutes then it stutters and I have to turn the car off and on. I'm working on getting the O2 voltages and I'll send the results this way soon.
 
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I've found the solution. I went to pull the O2 sensors and I found another vacuum line that escaped observation. It was rotted through and I visited my auto parts store and had them make a hose. I put it in and have had no issues whatsoever. Thanks for yalls help and hopefully I don't have to revisit this post lolz
 
I'm back again, the issue seemed to resolve itself for a while until now. It's back. I have replaced or deeply checked vacuum lines, all 90 degree rubber elbows, did the valve cover gasket because it was leaking a bit. I can only think I have a ignition issue because cruise still works (relies on vacuum if I am correct). The spark plugs are about 4 years old but the car has been driven only about 20k miles in that time. Should I do spark plugs and possibly the coil while I'm at it? Is there any way to check the coil?
 
You may need to put an infrared thermometer on your catalytic converter’s -
 
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I replaced all the 02 sensors on my 04 X with 68k miles, because I was already in there and NTK parts were running out. I can send you the fully functioning originals if you'd like to pay shipping and try out the 02 sensor route. Sometimes parts cannon actually works.