Foosh

GM has researched this issue and found multiple cases where the fuel sender sensor submerged for long (several months) periods of time, has become contaminated and no longer works. Obviously, it doesn't happen on the majority of stored cars, but the radical and expensive repair procedure is not worth taking a chance on.

Skid Row Joe

You're going to have to find out the over under time defined as storing. What is storing? 7 days is storing, so is 7 years.
.1/2 tank doesn't mean less than 1/4 tank, for storing.

Zjoe6

Make sure to not read the manual either. Good luck.

The Successful Plumber

What is this thing you guys call “WINTER”?

Water actually fell out of the sky here and it got real cold, 50 degrees. I didn’t drive my car for two weeks, but thank goodness it started right up.

phalse

Yeah, here in San Diego the only car storing we need to worry about is finding a damn parking place when I take my woman out somewhere.

You guys are doing things the hard way. Why live somewhere so cold? =D

Gearhead Jim

I've been looking and can't find anything from GM about this matter.
The Owner Manual for our 2017 talks about protecting the battery during storage but nothing about how much fuel to keep in the car.
One individual Tech has been vocal about storing with low fuel, but I can't find anything from GM to back him up. And the Corvette Techs in our area, where most Corvettes get stored for the winter, do no suggest storing with low fuel.

Do you have a link to the tech bulletin or the GM research? Those would be good reading.

Flame Red

Because we cannot afford the housing costs, high taxes and we refuse to submit to your commie/socialists politician's laws.

Seems to me the c6 setup is similar to the C7 setup and as I recall, the consensus of the C6 was to store them full - primarily so there was less exposure to air and humidity that could cause problems?

JerryU

If it's found great. BUT try this logic:
Of the 3 bullet benefits of Techron, this is one:
Cleans, restores, and protects the entire fuel system, including sulfur-contaminated fuel gauge sensors

In "days of old" you were keeping the tank full when stored to keep out moisture. Today the tank and fuel systems are sealed so no vapors can get I the air. That means no moister can get in!

IMO you can wait until told by GM to keep that tank below 1/4 full (and admit if they used gold plated resistor wire the sulfide problem would not exist)- or just use logic and say why not!

I do and don't store my car so the fuel is sloshing that "according to the article I read, not from GM" helps avoid the sulfur build-up. For me, I add Techron as insurance. Some have added it to solve the problem. In some cases it worked. In some the dealer dropped the rear drive train, dif, suspension and torque tube to drop the tanks to then replace the sender. Your car our choice!

For those doubting Thomas's:
Technical service bulletins and the National Highway Traffic Safety Administration re sulfur in the fuel.

What is happening? The silver in the sending units is tarnishing just like your good knives, forks and spoons. That is why silverware comes on those lovely boxes lined with sulfur-free cloth.

Silver reacts readily with sulfur compounds to create that tarnish--silver sulfides. Though it is fairly easy to clean off (remember cleaning your mother's silverware?), it is difficult to keep it from returning.

Fuel sending units suffer the same fate, and the problem gets worse in the heat.

Chevron Techron additives. Chevron Techron Concentrate Plus is the product GM dealers use.

We spoke with Scott Cushing, fuel system additives manager at Chevron.

And even the "top tier" gasolines, those with high doses of additives, don't adequately protect, according to Cushing. They don't have the filming agent. This coating, which is left behind, protects the sending for around 3,000 miles. "We suggest that motorists treat their fuel every time they get their oil changed," said Cushing.

Cushing says two tanks treated with the Chevron product usually can clean sulfur deposits from the sending unit and should be blended at a ratio of about one ounce per gallon of gasoline.

Ozzstar

No stabalizer for my car. Full tank of gas over the winter like I have done with every car I have owned for the past 30 years. No problems at all. Isn't that a miracle?

Foosh

I don't have a link handy, but it was much discussed here a year or so ago. There may have been an "Ask Tadge" question about it.

Skid Row Joe

What is the actual failure or part that takes place, and why can't the part be replaced with a durable one instead?



..

Vet Interested

The same reason GM uses some cheap parts on various generations of Corvettes.....$$$$ and it seems they would never admit there is a problem.

JerryU

Fuel senders have used a resistor with a wiper since I saw one many, many years ago! If you read the National Highway info it says the silver on that resistor forms a silver sulfide deposit. That is why I said in my prior post GM would admit IF they used gold planted wire it would not be a problem! Just my guess as gold unlike silver will NOT form a sulfur compound! That is why Tutankhamun's Headpiece still looks new after ~3000 years!

As I say no problem in the vented tank in my Street Rod. IF I have a problem with the sender (which I installed) a few bolts and I can remove the tank and replace the sender. The issue with the C7 is the car has to come apart to get the tanks down! Sender is cheap! All that work by the dealer and the HOPE it gets put together right, not worth it even if on warranty.

I chuckle at all those who say I filled the tank for ~30 years and no problem (why bother to understand the tanks are now sealed and NO need to have the tank full!) Reminds me of saying, "I have not had an accident with another car in 60 years of driving -TRUE!) I still watch out for all the AH's distracted on their cell phones. I have my iPhone set to not receive calls when moving so I can watch for them!

Gearhead Jim

I can recall much discussion over the last several years, also including the C6 section. But I can't recall any published research from GM on the subject, nor hearing about any GM technical bulletin. I just went through the Ask Tadge section and didn't find anything.

If anyone can find a link to those, please let us know.

xwing

I do it every year early Dec - mid March. No problems in 17 years (14 of them in the same Vette)...

pickleseimer

x 2

GShunter

Hello fellow Michigander,
I store my car with a full tank and stabilizer. never had any issues.

Kevin A Jones

Isn't that the TRUTH

Foosh

I don't think it's overblown. It's just a sharing of info of something that could happen, but probably won't. In this case, if you're one of the few unlucky ones, your car is going to need extensive disassembly to correct it. It certainly caused a lot of angst for the unlucky ones. Process the info, and make your own decision.

I NEVER store cars for long periods because they all get driven at least once a week, year-round. If a car is driven with fuel routinely sloshed over the sensor, it's going to stay relatively clean. However, if I did store it for 6 months, I'd probably not store it with a full tank.

krwunlv

One or two instances of storage won't impact sensors that much because it takes time for particles to build up. Much like eating a burger or steak every so often won't mess with your LDLs. However, if you eat 16 oz rib eye for dinner every day, McDonalds for lunch and sausage and gravy for breakfast every other day in your life... your going to see effect. Same with contaminants in low grade, cheap fuels, they are there and they will build up over time.