P0505 code question


1Salty Dawg

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New guy here. My new to me 1999 TJ auto. 4.0 is throwing a P0505 code gas gauge reading empty when full and CEL on. Jeep runs fine, no hesitation, spitting or loss of power. Starts right up on first try every time. I took out the IAC valve which looked brand new and still cleaned it up any way but no change. Any one have any ideas? Thanks
 

JMT

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New guy here. My new to me 1999 TJ auto. 4.0 is throwing a P0505 code gas gauge reading empty when full and CEL on. Jeep runs fine, no hesitation, spitting or loss of power. Starts right up on first try every time. I took out the IAC valve which looked brand new and still cleaned it up any way but no change. Any one have any ideas? Thanks
Did you clear the code by detaching the negative battery cable for about 10 minutes or using an OBD II Scanner?
 
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1Salty Dawg

1Salty Dawg

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So I disconnected battery for 10 mins and now the gas gauge reads over full and CEL still on. I had filled it up initially and drove about 50 miles when I bought it so I feel it should read just under full. I am going to check connections at the throttle body and see what happens.
 
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1Salty Dawg

1Salty Dawg

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So I am right back where I started my original post. Runs good, no RPM fluctuation etc. I feel there is nothing wrong with the IAC valve at all. Help.
 
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1Salty Dawg

1Salty Dawg

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Is the CEL, gas gauge reading empty and P0505 all related? I feel they are, I did the gauge test and all gauges seem to work with that. I took positive cable off for 10 mins and then start the Jeep and gauge goes to full. Turn off Jeep and restart and gauge reads empty. I checked where the wire harness at the fuel tank is and seems tight with no visible wire damage. The scan tool I have is generic at best so it says it is clearing the code but doesn't.
 

TJ Jim

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I think I’d chase the gas gauge problem and see if that solves the 505. Maybe the grounds for the gauge?