Hello and welcome to JustAnswer!
what year, model, and engine do you have?
Unrelated issue... same vehicle.
Went through several huge puddles (lol... lakes???) while running a "victory lap" in the parking lot at an opponent's football stadium last year. Since then, we have a couple issues...
Gas tank gauge slowly drops to empty, even when full.
Major vapor build up in tank when removing cap (assuming water in tank)
at about 1/8 tank, vehicle loses power, stalls, and becomes sluggish. (again, assuming water in tank)
Ok, no problem. The diagnosis is the same, but the relay is in a different spot. Its about the size of a deck of cards only taller. Its mounted to the metal bumper support on the driver's side with rivets, and has aluminum heat sink towers on the top of it.
The fuel gauge and the driveability problem probably run together. Its probably running low on fuel and running lean because the gauge isn't reading right. It could be wiring, the fuel level sensor or voltage bleedover between pins of the module connector. This was pretty common on some of the later RS body style minivans.
Some pressure or vacuum in the fuel tank is perfectly normal. There is a system in place that monitors the fuel tank and vapor lines very closely. It has the ability to pressurize the system to check for leaks, and it can pull vacuum on the tank using the purge solenoid, when its turned on to burn fuel vapors in the engine. If you had a problem there the engine light would be on.
Engine light is on. Assuming fuel level sensor got knocked loose from major water pressure ( or shorted it out )? Is this something I can fix? Do you recommend I get it put on a diagnostic first?
BTW>>> fixed relay! everything okay so far.
Lets see why the light is on. Cycle the key from off to on three times ending with it on and watch the digital odometer display. The codes start with a p and have four numbers, there may be more than one code stored. Write down any that you see and post them here.
My girlfriend has the vehicle at school at the moment. I will check for the trouble codes when she gets home (around 25 minutes or 2:35 pm EST) and post them.
Ok. These are nothing to worry about. The P1491 was for the fan relay you already fixed, and the P1684 was from disconnecting the battery.
You've either got a bad sending unit or a wiring problem to the tank. You can slide under the van and take a look at it. The top of the pump can be seen from the right side of the fuel tank. Unplug the connector and look for signs of water or corrosion inside, and check out the wiring. If its ok, the best thing to do would be to check the wiring over to the pump as far as you can, and if its ok its probably a sending unit problem.
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