'99 & up 7.3L Power Stroke Engine and DrivetrainDiscussion of the 99 & up 7.3L Power Stroke diesel engine and drivetrain in the 1999-Up Super Duty trucks and Excursions. No gas engine discussion allowed except on transmissions and drivetrain that pertain to all models. Please confine discussion of topics in this forum to those items that are specific to the 7.3L Power Stroke engine.
In my 99 Ford 7.3 the fuel gauge on my dash is stuck on Full. When I turn the key off, it goes to empty, but during driving and when the key is on it is all the way to full. Is this my sending unit or in the panel? Ford quoted me around $500 for a new sending unit.
Check the wiring back to the tank. If it's broken, the fuel gauge will read full. The sender is a resistance deal, with 160 ohms being full and 15 ohms empty, so a disconnected sender reads full when you turn the key on.
If you can get at the sending uint plug, measuere the resistance across it and see what you come up with.
It's also possible that the float got stuck up against the top of the tank. If it happened when you filled up, and have run some of the fuel out, crawl underneath with a rubber mallet and whack the dickens out of the tank. That may dislodge a stuck float. Worked for me the first two times I had a problem (4x4 launches on the drag strip without a completely full tank).
You shouldn't have to buy a whole sending unit to fix your problem. I think you can take out sending unit and replace the the resistor unit. I know on the older trucks, it was held on to the sending unit with a couple of screws. I did this on my brother-in-law's truck and got the piece from Ford.
2005 F-350 CC, LB, 4x4, Dually, 6.0 Powerstroke, Torqueshift, 4:10 Gears. Gooseneck and rear pull hitches. "Truck Covers USA" roll up aluminum tonneau cover. Putco Boss Running Boards. Aluminum finned diff covers. Bilstein HD shocks. ProComp steering stabilizer. XRF ball joints. NC Hornet CCV mod. RCD egr delete kit. AirDog fuel system. Strictly Diesel's regulated fuel and coolant return lines kits. Amsoil oil bypass (by NUC Motorsports) and homebuilt coolant bypass kits. CFM intake elbow. ARP head studs with factory gaskets and all upgrades. FICM by Ed with Atlas 40 tune, DC Power 185 amp alternator, MBRP 304SS "Cool Dual" exhaust system. SCT Livewire tuner with pyrometer. Autometer 'A' pillar gauges (Boost/Trans temp/Pyrometer/Fuel Pressure). 850 CCA Motorcraft Batteries. Using Rotella T-6 synthetic oil. Upgraded degas tank and cap. Hayes deep aluminum trans pan. GoGo Diesel modified direct clutch solenoid. Retro Solutions HID head and fog lights. High idle mod. Jimmi-Jammers. +More.
I am going to try beating on it and see if that does anything. I think I would have to take the tank out to actually get to the sending unit to test it.
It was actually on empty, I left town for 2 weeks and came home and it was on full.
You don't think someone was kind enough to have filled er up while you were out of town?
I dunno if there is a connector somewhere between the tank and the dash, but if there is, that is another place you can ohm out the resistance of the sending unit. I "think" if the wire is gounded anywhere it will show full. Also, does the guage show "super full" - like its pegged above full, or something else?
__________________ TDS member #49 - 1999.5 (Built 4/26/99) White F350, CC, SRW, LWB, Lariat, AIC, 4R100 (4th transmission before 85k - gotta love this tranny), 6.0 trans cooler, manual shift 4wd, 3 inch leveling kit, KING reservoir shocks, 285-75-16 Bridgestone REVOs, Performance Friction Pads all around, Powerslot Cryo'd rotors in front, CD player, Infinity REF 6800CS speakers (front and rear), Garmin 2610 GPS (hardwired), 40/20/40 leather seats, heated turn signal- TT mirrors, Titan V hitch, weatherguard box, DP Tuner 4 Position chip (love it), AIS intake, Diesel Site CAC Boots, 4" Magnaflow exhaust, Diesel Innovations Up Pipe, gutted EBPV, Non EBPV Turbo Pedestal, X-Monitor. NO STEERING WHEN BRAKES ARE APPLIED!
I "think" if the wire is gounded anywhere it will show full.
Actually an open circuit anywhere between the sending unit and the instrument panel will cause a full reading.
As I recall, the connector on the fuel tank can be disconnected with the tank in place and pulled over far enough to probe with a multimeter. The only trouble is you need 2 elbows in each arm to reach up there, and you have to use the braille method to see what you're doing.
I've never actually tried it, but have had the tank down a number of times and there's a fair amount of slack in the wiring.
Same problem with my sending unit - been ignoring it for a long time (use the trip odometer for miles driven)....but I need my 'quick reference level' back for heavy towing.
I'll check the wiring, but I'll run the tank low and drop it that way I can check the float as well.
99.5 F350 Scab, 4x4, Lariat, short bed, 4" MBRP w/ 'bling' and I was going for a no-bling-thing, Hutched/Harpooned tank, Kwik/6637 intake, CCV mod, 203*, Evans, coolant filter, Fumoto Valve, International up-pipes, 52K miles and counting.
On a lot of trucks it is easier to unbolt the bed and raise it than remove the tank.
2000 F350 srw pickup
3 in. leveling kit,35x12.5x16.5 BFG's,K&N air filter,4 in. exhaust from turbo back,Bully Dog boost,trans temp and exhaust temp gauges,Painless wiring inline module,Western Diesel four position chip(currently out being repaired),203 thermostat,Bully Dog shift kit.