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Discussion Starter #1
my jeep just now starting running sluggish shakes when im driving has no power and oil pressure is at 80
 

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Discussion Starter #3
Found the problem #1 cylinder misfire
 

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Discussion Starter #5
Well not exactly changed all plugs and it's still not working
 

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Check ur throttle body and clean f its dirty- wha i would also check is to see if ur injectors are gettig fuel- there is a little nozzle covered by a plastic cap. Take the cap off and push the valve in- if u have fuel coming out thst means your fuel pump is working- maybe a bad injector i think
 

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Discussion Starter #7
The throttle body would cause cylinder 1 to miss fire?
 

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Nope not at all but aince you changed your plugs and that didnt work i would look to fuel- throttle body dirt and or gummed up injectors.
You could also check your wire to #1 plug and the distributor- im just trying to see if you are having fuel issues since you changed plugs...
 

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Discussion Starter #12
Ima look at my injectors tomorrow
 

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Discussion Starter #13
Just from Ccylinder 1 miss firing would be my coil pack?
 

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Discussion Starter #15
i did a spark plug test on all plugs all look the same still throwing same code so i changed an injector to see if that helps it starts alot quicker with the new injector but still running sluggish and i also noticed a weird smell coming from my exhaust
 

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Is the misfire code PO300 or PO301? If it is PO301 then it is specific to cylinder 1 PO300 is random misfire. If you already changed the plugs/ inspected or changed the wires the next step in diagnosing the problem is code dependent.

For a random misfire check things that affect all cylinders, fuel pressure, vacuum leaks, throttle body, fuel filter, O2 sensor, etc.

For a specific misfire check the coil pac, injector, compression, cylinder leak down, etc..

Remember that after changing a sensor or computer controlled component that it will take several miles for the appropriate computer to calibrate the new part. I have seen the check engine light come on from a component being replaced. Sometimes it just takes a lot of time to get everything working together again.

Best of luck.

Jeremy
ASE Master Auto Technician
 

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Discussion Starter #18
It's not random missfire it's the 301 code
 

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It shouldn't be the coil pack for cylinder #1 because cylinder #2 is not throwing P0302. There is 1 coil pack for every 2 cylinder in the 4.0l . Check your injector plug with a noid light first. If it lights up then electronics is ok. Check the ohms for each injector. Each should be within the same range. If all is ok, then check compression. You may have a leak in cylinder 1.
 

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If 1 injector is replaced, disconnect battery to clear PCM memory. Turn on headlights for 5 seconds to completely discharge remaining power left in the PCM. Reconnect battery and drive jeep for 20-30 miles. Computer has to relearn again. During this phase, the computer will be using the default settings until it has logged enough data points. Do not plan on smog checking it until after driving 50 miles because it will fail.

If you do not want to drive those many miles, the other option is short trips with several start-ups. I can't remember from the FSM but I think it will take 40-50 starts.
 
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