L-EATER

iTrader: (2)

I pulled the fuel pump module on my truck and installed a dual in tank pump setup yesterday. I reused the existing gauge sender and have never had any probs. After I finished install, I fired it up and noticed the low fuel light was on and the gauge was on empty. I pulled it all apart again to check the floater, thinking I must have messed it up during the install. Anyways, all was well and I checked the output of the sender with an ohm meter and it is ok.

I put it all back together and fired it up again and the check engine light starts flashing so I hook up A-tap and it has codes 300 (random misfire) and 463 (fuel sender high voltage, or something) Service manual says that when 463 sets the gauge will default to empty and the low fuel light will come on.

My diagnostic capabilities are limited with the A-tap, but like I said the sender checks out with a dvom and if I clear the codes the gauge works fine til the codes return. What in the heck is going on here??

L-EATER

iTrader: (2)

anybody?? what is the connection between code 300 misfire and the code 463??

L-EATER

iTrader: (2)

Well, I ordered a new fuel sender from the dealer and what do ya know-no more codes and the gage works fine again. Who knows why these things are so dang sensitive...

Another_User

I doubt there is a connection. The misfire code is caused by your cam. It probably only showed up now because you have been idling for long periods of time trying to figure out what is going on with the fuel pump. Are you sure you wired everything right? It's possible the sensor went bad I guess. P0463 is "Fuel Level Sensor Circuit, High Input". Your output may be fine, you need to check the input.