Hey guys, haven't posted here in a while..been out of town working and avoiding spending anymore $$ on the dak, but its time to do so again lol


Over the last few months, my gas gauge has been way off. Its getting brutal and a little nerve racking as all the roads and highways close to me are up and down mountains, and the 4.5 hour drive I commonly have to do goes from sea level up to 5000 ft twice. Ive had this truck for 4 years, before it I had a sebring so im aware that these gauges are typically somewhat inaccurate.

Right now Ill drive 180-200km (110-120 mi) and my gas light will come on. Ill fill it up, and it will take 36-44L (10~ us gallons). The gas gauge shows that I'm down to half a tank after driving 100km (60~ miles). Sometimes when I park for a while turn the truck on it will go back up to 2/3 - 3/4 of a tank where it should be. 5 or so times in the last year I've turned the truck on and the gas gauge sat at empty (happened when Ive had anywhere from 1/8th of a tank to a full tank) for sometimes a few hours or sometimes just a couple minutes. Right now, I've driven 220km and its sitting on a scary level of empty. It makes it a pain in the *** on road trips, especially this winter when I've been needing 4x4 along some of the mountain passes fully loaded bed, not sure if I've actually burned through that much fuel or not. The gauge doesn't move spiratically so I dont think its a bad wire/ground.

Its annoying as hell to only get 100 miles or so on a tank before the light comes on, any suggestions on what it could be? Sending unit? Is there an adjustable float on these fuel pumps?

Thanks guys

 

The float isn't adjustable.

Try a cluster test to check the gauge calibration (just the gauge, not the sender to the gauge). Key off, press and hold the trip reset button in, then turn key on (not start) while holding it in until you see CHEC in the odometer (takes about 10 seconds).

I had the same problem years ago. I ended up replacing the pump assembly. The contacts on the sender had been damaged by something in the gas, there was a rash of these 10 or so years back. It's not that bad a job if you pull the bed.

 

Just went out and did the gauge calibration as you said- it checked everything and all the gauges moved the way they should, including the fuel gauge. However, it went from being around E with the gaslight on to a little more than 1/4 tank; where it should be. So..so far so good. Ill keep tabs on it over the next couple gas tanks and see if that gauge calibration makes the fuel gauge more accurate. Ill post a follow up a couple gas tanks from now. Thanks!

 

It doesn't set the gauge calibration, it just tests it. But, maybe the needle is sticking and the swing loosens it up some???

 

I am thinking that the ground going to the sending unit is loose, and the resistance of the poor connection is causing the bad gauge readings.

 

Well..the gauge calibration test only works occasionally, its not very reliable lol. Any idea where the fuel sending unit is grounded? Ill trace all the wiring & check the ground connection. My last resort will be to drop the tank and check the actual fuel sending unit terminals..im hoping the problem is elsewhere though!

Is the fuel sending unit grounded on the frame?

 

If it's like later years it does NOT ground to the frame. The feed comes from the PCM and returns to the PCM.

 

Okay i'm just about to go check it out..I guess if I cant find it grounded to the frame and the wires are in good condition with no breaks then it will be the connection on top of the fuel sending unit (yippy!)

thanks

 

Apparently what can happen is that sulphur in the fuel tarnishes the silver contacts on the fuel sending unit. That's why mine died but there was a rash of this a few years back.

I'm not a fan of additives but, Techron claims:

1. Cleans sulfur deposits from gas gauge sensors
2. Protects gas gauge sensors from malfunctioning

It might be worth a shot.

 

Yeah I put some Rislone gas additive in earlier. It showed that I had 1/8th of a tank after driving only 100km..I used my cell phone camera w/ flash to check the connectors ontop of the fuel pump..no obvious disconnects or anything. Googled a few pictures of the fuel pump assembly and where the sending unit is.. Techron seems to be the consensus product to fix the problem. Ill try it out the next gas tank or two to see if it does anything..Ill gamble the $20 to avoid pulling the bed off the truck/dropping the tank.