2001 TJ Sahara running rough

jamesg7

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Aug 27, 2020
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9
Location
Maryland
I have a 2001 Wrangler 4.0 that despite my replacing many parts, is still running very rough. So a few hundred miles after I had the transmission rebuilt and the torque converter and crank sensor replaced, I developed a problem. The check engine light started flashing, the engine made a horrible rumbling sound and I lost half of my horsepower. I took it to the shop and they said the new crank sensor was faulty and replaced it. A hundred or so miles later and it did it again, took to a different shop and they couldn't find anything wrong and said it runs great. Another hundred miles later and the problem changed and is my current problem. I have no check engine lights on but it seems like the motor is not running on all cylinders. It runs horrible in idle, I have about half of the horsepower, and everytime I slow down to a stop it either stalls or almost stalls, I can stop it by putting it in neutral. I've read some of the forums and I have replaced the spark plugs, the ignition coil and the throttle position sensor. After I replaced the plugs it did run perfect for about a day, then back to the same. Now I dont know what else to try, please any suggestions are appreciated.
 
What codes is it throwing and what brand of replacement sensor did they use?
 
Since replacing the plugs fixed the problem for a day; I would remove a couple plugs to see what they look like. IF they are black with carbon on them; then the engine is running very rich...
 
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What codes is it throwing and what brand of replacement sensor did they use?
I assume its not showing any codes now because the check engine light isn't on, but when I had the problem the first two times they said it cleared itself but showed in the history a misfire code in cylinders 3 and 4
 
Since replacing the plugs fixed the problem for a day; I would remove a couple plugs to see what they look like. IF they are black with carbon on them; then the engine is running very rich...
I didnt try that, but I will say that the plugs I replaced looked pretty good, not very dirty or burned up