Tioga Won't Budge after long neglect. Help, please.

211Racing wrote:
That would be a good guess, but it's fuel injected. 5.4 V8.

Thinking I've got a vacuum issue. Might need to trace the vacuum line back to the engine and see if I loosened a fitting when I was lowering the tank the first time and didn't know all the lines were so darn short.

Working against that theory is the fuel gauge on the dash not registering the 8 gallons of gas I added before starting it up. Still read empty. Still had a "LOW FUEL" light on the dash. The new Delphi Fuel Pump looked and read to be an exact replacement. That's why I chose to replace it completely rather than rebuild the original pump. Other than the "LOW FUEL" light, it is not showing a "CHECK ENGINE" light. I will replace fuses today and see if I can get everything powered up again. Have a Foxwell scanner I just updated with all things FORD. Will see what that shows.

Well you have made some progress, graduating from spraying starting fluid from a can.

Check the fuel rail pressure, typically on 5.4s it should be 40 PSI take or give 5 PSI.

To high or too low and the engine isn't going to run right and could be the pressure modulator (regulator) as Ford calls it. This could be a mechanical regulator or electronic, not sure on that. 2004 up to 2008 they used a electronic control mounted around the rear axle on pickup trucks.

"pumping" shouldn't make a difference typically but doing so you are adding extra air (WOT) and altering the throttle plate sensor reading and computer will alter the injector timing to allow more fuel or less fuel.

2002 5.4s have a very "basic" crude OBD2 system implementation with minimal sensors and data which tends to make troubleshooting less automated and more hands on. Basically it is the equivalent to OBD1 but with a OBD2 connector. I no longer have a 2003 so I can't verify if the OBD2 system has fuel pressure reading for the earlier yrs.

Nice write up! My fill and vent hoses are 1 piece.I cleaned them up with some lacquer thinner and they will be OK.The parts store replacement filler is too thick and not pliable enough to work.
My main concern with the tank removal was spinning out the heads of the carriage bolts on the passenger side.Driver's side has U nuts over the frame and the bolts should come out.Nothing was real rusty.I do have a transmission jack that should work but I guess I will have to struggle with the rest of it like you did.
I think I mentioned in a previous post something about the gas gauge not being correct with the complete pump and housing replacement.The fuel pickup might not be low enough to suck much gas with 8 gallons.If that vacuum line is pinched , disconnected,or damaged,it will throw a fault code but the engine will still run OK.

That would be a good guess, but it's fuel injected. 5.4 V8.

Thinking I've got a vacuum issue. Might need to trace the vacuum line back to the engine and see if I loosened a fitting when I was lowering the tank the first time and didn't know all the lines were so darn short.

Working against that theory is the fuel gauge on the dash not registering the 8 gallons of gas I added before starting it up. Still read empty. Still had a "LOW FUEL" light on the dash. The new Delphi Fuel Pump looked and read to be an exact replacement. That's why I chose to replace it completely rather than rebuild the original pump. Other than the "LOW FUEL" light, it is not showing a "CHECK ENGINE" light. I will replace fuses today and see if I can get everything powered up again. Have a Foxwell scanner I just updated with all things FORD. Will see what that shows.

Runs only if you pump the pedal...
Carbureted engine (Guessing it is) metering jets clogged. Only the acceleration pump feeding fuel to the throttle body.

Much to share. Not all of it good. Almost all of it educational.

Will start with your question(s) and follow with play-by-play.

The filler and vent hose ... They were deteriorating but still functional. Covered with black powder that I guessed was the outermost rubber failing. Important note on my rig was that there are two places where there are short runs of rubber line/hose. First is where the fuel tank filler neck and vent hose take a hard turn from the inside of the RV wall to the metal line that turns and then connects to the fuel tank with two more short runs of rubber line. Hose source? Measure the internal diameter of the hose and either order off Amazon, or better still take it into your local autoparts store and put it on them to get you the correct size.

Removing the tank: Took great energy and a fair amount of ingenuity. WARNING. There is virtually no slack on the three fuel lines that connect to the fuel pump. If you don't have long slender arms with great grip strength, find someone that does. You need to reach up over the frame, on the port side of the tank, where there's about 4" of clearance, and blindly detach the fuel lines. Same for the electrical connection to the fuel pump, which mounts on top of that frame rail, and the Fuel Pressure Sensor which also runs up over that rail. There are also two vacuum hoses that attach to two separate ports, but they had a bit more slack. I cut new vacuum hoses a wee bit longer and that helped a little in reassembly.

Dropping the Tank: It's heavy. I would guess 200lbs. Maybe 250. Completely drained it. Six bolts hold it in place. Don't be distracted by the additional three bolts on the starboard (passenger) side that clamp the tank together. Do not touch them. They do not need to be loosened and will not loosen. I used three jacks to get the job done. One 12 ton bottle jack to raise the port dual wheels so I could get under there and work, and two racing jacks positioned at the front and back of the tank to lower it. Plus lots of jack stands to keep me from getting crushed. Once the tank was down I used a block of wood and a rock as a lever and fulcrum to get the racing jacks out, then dragged it out from under the RV. I had dreamed of doing it all with the tank just resting under the RV, but that was impossible

Once the tank got out into the sunshine, things got ugly. As mentioned previously all six bolts sheered off trying to get the old fuel pump off. I ground flat, drilled and tapped the remaining bolt stubs which were welded in place on the inside. The only apparent torque needed on these six bolts is to compress the rubber gasket that seals the pump in place (I hope). I was fortunate to find a new Delphi fuel pump that was a visual match to the old pump. I also replaced the fuel pressure sensor with an identical unit.

Replacing the tank: There are two welded-in-place eyelets on top of the tank in opposing corners. I took two cargo strap ratchets and hooked them forward and aft of the tank, hooked them to the tank, and routed them up over the frame. Was able to raise it up enough to place the racing jacks back under the tank. It took about 12 attempts to position the tank so it would exactly match up to the holes (port side) and bolts (starboard side). Reattaching the three fuel lines and two electrical connections is again challenging in that you need to do it blind by reaching up over the frame once the tank is in place.

NOW FOR THE HEARTBREAK! Got it all together. Turned the key. Started with a little pump on the gas pedal. Ran rough. Could keep going if you pumped the gas. No pumping the pedal meant it stalled. About the third start I was pumping away, thinking I was clearing a fuel injector issue, when I heard BEEP BEEP BEEP, and everything went dark. Zero power to anything. I gave up and went in for the night.

More soon.

How's the project coming along? I've been following your thread.Anyway... My E450 has been sitting since last fall so I thought i'd get it running and check things out.Guess what.Crank no start,fuel pump.My setup looks exactly like yours.One question...Was the filler and vent hose covered with some ungodly black stuff that you managed to get all over yourself and everything else you came in contact with,like carbon black?Did you find a source for that hose? Thanks!

That's good advice. The inside of the tank looks great. A small plus is that the rubber filler hose and what I'm assuming are rubber vacuum hoses were looking pretty bad. Will replace all. One less thing to fail from decay out on the road.

Well, thats kind of ugly..

Since you have it down, brush off any loose rust and treat it with a rust converter. I use Ospho which converts the rust to a black paintable surface. Once treated with a rust converter the rust will not come back or creep.

Treat any place where you see even light rust on the outside of the tank with a rust converter..

All rust converter treated areas must then be topcoated with paint for maximum durablity.

Consider painting the entire top of the tank with a durable paint like a rubberized bedliner.. Harbor Freight believe it or not carries their own bedliner paint in a can that is pretty tough. Do not use Rustoleum bedliner, it is junk, it is nothing more than textured paint, it is not rubberized and scratches easily.. I would suggest using bedliner on the entire outside and even the tank straps for good measure.. I live in the rust belt, steel tanks tend to fail on the tops and where the tank straps touch the tanks..


The pix showing the inside looked OK but if you can see any spot inside the tank that has signs of rust you may wish to consider using a tank liner system..

Por15 products makes a tank liner paint system that holds up well to Ethanol.. It is a multi stage/product were you must use a Etching/cleaner then the actual tank liner.. With Por15 tank liner products you need to read and follow the instructions to the "t".

Tough day. Pulled the tank. Removed all the lines. Pulled it out from under the RV. Soaked the Fuel Pump bolts with Kroil. Waited a couple hours. Tapped on them a bit to loosen. Then proceeded to snap all 6 off with maybe 10lbs of torque. Two were almost completely rusted through as you see in the image. So ... time to clean all that up and drill/tap those bolt heads (which are welded on the inside). Three of them I almost off until the metal fatigued and failed. Two steps forward, one step back.

Click For Full-Size Image.


Click For Full-Size Image.

That's good intel. Thank you.