Check engine light only comes on when gas tank is 1/4 full

Just the light —— and only comes on when it hits a 1/4 tank —— What else should I post-— I am lost
So if the light illuminates and PO301 is the code in the ecu if you could go out and pull the plug wire from cylinder one, would it make a difference in the engine smoothness or not?

Trying to determine if the cylinder is actually miss firing.

Just to note the crank position sensor is what helps identify a missfire IIRC. What anything done with the crank position sensor recently.
 
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Just the light —— and only comes on when it hits a 1/4 tank —— What else should I post-— I am lost

No running rough? Power loss? Hesitation? Surge?

P0301 is a misfire code, should run bad, at least for a moment.

I don't see a correlation between the 1/4 fuel level and code though, that's odd.

I would probably keep the fuel level above 1/4 for awhile just to make sure it wasn't a coincidence and see if code returns.
 
No running rough? Power loss? Hesitation? Surge?

P0301 is a misfire code, should run bad, at least for a moment.

I don't see a correlation between the 1/4 fuel level and code though, that's odd.

I would probably keep the fuel level above 1/4 for awhile just to make sure it wasn't a coincidence and see if code returns.


It is very odd... I traded for this jeep three weeks ago. Passed the Nevada Smog check, what a joke that is, just fine... Twice now, tank hits 1/4, light comes on. Fuel up, about 20 miles or so of driving light goes off. Back to a 1/4 tank light on-- repeat about 20 miles drive, turn off restart light is off ———
 
It is very odd... I traded for this jeep three weeks ago. Passed the Nevada Smog check, what a joke that is, just fine... Twice now, tank hits 1/4, light comes on. Fuel up, about 20 miles or so of driving light goes off. Back to a 1/4 tank light on-- repeat about 20 miles drive, turn off restart light is off ———

Interesting. So do you always fill up at 1/4? Have you tried running 20-30 miles past just to see what happens?
 
I don't know what low fuel and a misfire could have in common, but the first thing I would want to know is if cylinder #1 actually misfiring. I would, as @Fouledplugs suggested, when the light comes on pull the plug wire from the #1 plug to see if the engine starts to miss. That would tell me if its misfiring. If it is really missing I would then connect a noid light between the #1 injector and its harness to see if the injector is getting its proper signal and ground.
 
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It is very odd... I traded for this jeep three weeks ago. Passed the Nevada Smog check, what a joke that is, just fine... Twice now, tank hits 1/4, light comes on. Fuel up, about 20 miles or so of driving light goes off. Back to a 1/4 tank light on-- repeat about 20 miles drive, turn off restart light is off ———
Just to note the crank position sensor is what helps identify a missfire IIRC. Was anything done with the crank position sensor recently?
 
Update to my problem —-
shop could not find a problem for this code. Everything checked out just fine. Getting piised about the light coming on I tried the old "Witch Hazle/Snake Oil treatment I have used for years... Big dose of Marvel oil down the tank and in the oil —- WTH —- Have not had the light since. Do not understand why BUT ok-— -no light and clean smog check for registration in Nevada ——