DGFisher91
New Member
I recently installed a Titan 50 gallon gas tank as well as a FASS 165gph fuel system on my 22 Megacab.
Obviously DTE / Fuel Gauge were off. Fuel gauge worked however, and would stay on "F" for the first 15 gallons or so and then go down as normal. Based on everything I read prior to install this was the correct behavior and to be expected.
Within the last couple of weeks I installed the KOADTech bypass and used the MX+ and AlphaOBD to adjust the tank size in the body computer. Note that this is the ONLY change I have made using AlphaOBD.
The update worked fine. Confirmed the change was successful, DTE went up as expected, no issues. DTE showed somewhere around 500 miles to empty (my tank was not full).
I drove it around for a week. I only travel 3mi to work so between that for 3-4 days and a couple small trips it wasn't surprising to me to see around 380 when I hopped in to take a 40mi trip saturday with the fuel gauge reading between 1/2 and 3/4 full. I do have to say though, I wasn't paying enough attention and was taking the DTE / fuel gauge as gospel and shouldn't have.
On the way home I noticed the DTE plummeting FAST. We went 2 actual miles and it dropped nearly 200 miles and went from 1/2 full on the gauge to E. I knew I had either punctured a line / tank / filter or something was wrong with the computer. However, truck was operating normally otherwise. I dropped from around 300mi to 11mi in about 10min of driving. We were on a remote stretch of highway where there are no gas stations close. So I coasted as best I could to get as close to home or gas as possible.
Pulled over, checked everything, couldn't find any leaks, fuses weren't blown. Had a buddy bring a couple gallons of gas just in case. Put 5 gallons in....DTE immediately reads 388.
I drove straight to the gas station and filled up. It required 42 gallons of gas plus the 5 we put in, so when it was reading "Low" when I pulled over I had roughly 3 gallons left, even though 10min prior it was reading 1/2 tank and 300 on the DTE.
Has anyone experienced this before? The tank and FASS system have been in the truck for a couple of months without issue. And to be clear, I installed the FASS properly with the new suction straw at roughly 1/8 - 1/4" from the bottom of the unit and everything was working well prior to the tank size change.
Is my sending unit bad (wiring)? Something else I can check? Should I have filled up immediately after the AlphaOBD change so the computer knew it was reading full?
Obviously DTE / Fuel Gauge were off. Fuel gauge worked however, and would stay on "F" for the first 15 gallons or so and then go down as normal. Based on everything I read prior to install this was the correct behavior and to be expected.
Within the last couple of weeks I installed the KOADTech bypass and used the MX+ and AlphaOBD to adjust the tank size in the body computer. Note that this is the ONLY change I have made using AlphaOBD.
The update worked fine. Confirmed the change was successful, DTE went up as expected, no issues. DTE showed somewhere around 500 miles to empty (my tank was not full).
I drove it around for a week. I only travel 3mi to work so between that for 3-4 days and a couple small trips it wasn't surprising to me to see around 380 when I hopped in to take a 40mi trip saturday with the fuel gauge reading between 1/2 and 3/4 full. I do have to say though, I wasn't paying enough attention and was taking the DTE / fuel gauge as gospel and shouldn't have.
On the way home I noticed the DTE plummeting FAST. We went 2 actual miles and it dropped nearly 200 miles and went from 1/2 full on the gauge to E. I knew I had either punctured a line / tank / filter or something was wrong with the computer. However, truck was operating normally otherwise. I dropped from around 300mi to 11mi in about 10min of driving. We were on a remote stretch of highway where there are no gas stations close. So I coasted as best I could to get as close to home or gas as possible.
Pulled over, checked everything, couldn't find any leaks, fuses weren't blown. Had a buddy bring a couple gallons of gas just in case. Put 5 gallons in....DTE immediately reads 388.
I drove straight to the gas station and filled up. It required 42 gallons of gas plus the 5 we put in, so when it was reading "Low" when I pulled over I had roughly 3 gallons left, even though 10min prior it was reading 1/2 tank and 300 on the DTE.
Has anyone experienced this before? The tank and FASS system have been in the truck for a couple of months without issue. And to be clear, I installed the FASS properly with the new suction straw at roughly 1/8 - 1/4" from the bottom of the unit and everything was working well prior to the tank size change.
Is my sending unit bad (wiring)? Something else I can check? Should I have filled up immediately after the AlphaOBD change so the computer knew it was reading full?
