I have recently purchased a 2002 Corvette with 2800 miles on it and I am having some issues with the fuel system. When I fill the gas tank up, the gage reads 7/8s full, then after driving for a bit it slowly starts moving until the gage indicates slightly over full before declining erratically afterwards. More concerningly, I smell fuel coming from the right rear area of the car by the wheel after refueling. After driving for a bit, the car throws P1431, sending the gage to empty. I reset the code but it always comes back. It has also run out of fuel with roughly 6-8 gallons of gas remaining in the tank. I have tried the Techron solution before 6 fill ups to no avail. Any ideas on what could be causing this?

 

The P1431 is a faulty right tank fuel sender...if you add the Techron to a full tank it will not get into the right tank...add it when the tank gets down to say
a 1/4 tank or less... the EVAP charcoal cannister is in the right wheel well area and also the EVAP vent valve is located in that area also. Also don’t overfill your tank and if you can get non ethanol fuel in your area use that with the Techron for a while !!

 

Sounds like it might be more than one problem, which is always fun to diagnose.

With respect to running out of gas with significant fuel left and attendant codes, it is likely that the jet pump in the right tank that transfers fuel to the left tank is clogged. There is a tiny nozzle inside where the motive flow from the main electric pump enters. Others on the forum have had success in cleaning the nozzle, but I just replaced the jet pump. Only supplied as an assembly with the right tank fuel sender.

 

I have no beef with Techron, but it is not the universal solution , it is only a solvent, mechanic in a can stuff.

If your car has a history of being fed crap gas that needs a solvent to clean up after, no problem. It also might have been a long term habitual low fuel situation that allowed oxidation to form on the sender, which uses a resistance coil and a wiper on a flat to generate signal. A solvent might help there, residues can gather on the electrified coil. reported to be sulphur deposits, if memory serves

The additive was originally developed to prevent injector clogging in a Porsche engine of long ago, and now every top tier gas has the additive. I would think most corvette owners run good gas, so Techron probably won't help what others have suggested is a mechanical problem.

I poured a lot of Techron through my tank , following the suggestions here, before it finally dawned on me that fuel residues were probably not my problem, since my issues remained unchanged and the car only sees top tier fuel with me, plus the previous owner carried around pictures of the car in his wallet , and more than enough money to fuel the car properly . As a practical matter, inferior fuel would be hard to find around the area where this car lives .

A transfer jet can be tricky, it uses only suction to draw a higher amount of liquid through the pump, and it has to be right. One guy reported a sliver of plastic film somehow got in the tank and jacked up his fuel transfer jet, and removing that small plastic film debris stuck to one side of the opening orifice fixed his deal. So be careful that parts of the bottle seal from whatever additive you favor doesn't shed into the tank.

I also have this common sender problem, but it never smells like a leak. Fixing the cause of the smell would be my primary concern, word in the hood is they burn real good, the car being plastic and all. Some production had an assembly problem with the seal at the top of the gas tank deteriorating with age, but you would have to look up the details.

In my case it appears the transfer between the tanks is out of design specs, and with constant long runs this causes the senders to read in such an imbalanced way that the computer cant understand the signal, so it trips the gauge to empty . This only happens with extended constant running, and can be reset with a stop and start with what seems to be a now correct gauge. since the connection is always open, I assume the fluid contained seeks a constant level. . I have read that the dealer can reprogram the computer to be more forgiving in reading the sensors , another solution is to just replace the old sensors for new.

if corrosion is the problem, reprogramming the computer won't do much. If one is running convenience store gas without top tier additives , Techron is undoubtably a good call. Some like Seafoam better for the same problem. None of that stuff worked for me, hopefully your problem is as simple as running some solvent, but that won't fix a leak.

All the best in fettering out your new ride. My used ride took some time to correct every little thing. Few people sell a perfect car.