Purchased my JKU (09 Rubicon) couple months ago. Everything works, Jeep drives great normally, no engine light, fuel gauge works.

Anytime the Jeep gets wet, the fuel gauge stops working and the engine light comes on. Code reader says P0463, which I believe is a rather generic code for a “high” circuit reading. Once it dries out, fuel gauge starts working again. I can clear the code with the reader and it stays off, or after a couple days it clears itself.

Friday we took the Jeep up a trail ride, about 3 hrs. Ran great. There was a creek crossing I hit at enough speed to throw water all over the underside. Jeep started running extremely rough, gauge stopped working, engine light came on. After a few minutes car started running fine again, gauge came back a few minutes after that. I’ve checked everything underneath. All plugged in and seen in good condition. Rig only has 53k miles on it.

Any ideas? Thanks guys!!

Matt

 

For P0463 like that I think there's a bad wiring/connector going to the fuel level sensor in the fuel pump module inside the tank. And since it runs bad at the same time, it probable involves the wiring to the fuel pump in the tank as well. Look for trail damage first, maybe from tree branches.

N4 and K900 are the wires going to the fuel level sensor. Stay in touch,

 

Thanks for the advice!!

Crawled around under her for the last half hour. Everything I can see or get a hand on seems to be ok. Everything is securely plugged in, no visible damage to any wires or hoses.

 

Maybe take a hose and spray areas under the jeep in certain areas to try and replicate the problem. That would help you find the area.

 

Code happened after changing my fuel pump one Month later clear the code and back again
shall I remove the tank its about 3 hours or drop a little to check the cable ?

 

Reading back to the original post and the followup from yesterday.....I think the only course of action in these situations is to drop the tank and inspect. You just can't get enough sense of how things are with that limited space while installed.

Sniper - did you install a factory pump or a cheap off-brand? I've installed a couple fuel pumps on other vehicles in the last couple years and opted for "cheap" cuz of the age and projected longevity of the cars. There was a pretty big difference in quality from OEM to the cheapies.

 

Sniper, if you decide to drop the tank for inspection, might want to pack the connectors with di-electric grease to help prevent water intrusion.