SkyBox

Are there any recommendations on fuel treatments to add to the tank? Bought car from a dealer with 6K miles and do not know what octane rated fuel was used in the car previously. Hopefully ALWAYS premium.

Zjoe6

Top tier gas has all you need. Mobil 93 is one good choice. If only 91 is available an octane boost is a good idea especially in outside temps over 90 F.

Elk

Do not waste your money by adding anything to the fuel.

The manual calls out 93 octane. But unleaded gasoline with an octane rated as low as 87 can be used. Using unleaded gasoline rated below 93 octane, however, will lead to reduced acceleration and fuel economy. If knocking occurs, use a gasoline rated at 93 octane as soon as possible, otherwise, the engine could be damaged.

SkyBox

The only reason I ask is because the manual states the following below, and for all I know the dealer put 87-89 octane in it.

Fuel Additives
To keep fuel systems clean, TOP
TIER Detergent Gasoline is
recommended. See Fuel 0 206.
If TOP TIER Detergent Gasoline is
not available, one bottle of Fuel
System Treatment PLUS added to
the fuel tank at every engine oil
change, can help. Fuel System
Treatment PLUS is the only
gasoline additive recommended by
General Motors. It is available at
your dealer.

Elk

Octane is completely unrelated to whether the gasoline is certified as Top Tier. Top Tier simply means the gasoline has more detergents that the minimum required by the EPA.

Lower octane will not have hurt the car, see my earlier post which you quoted.

Just use Top Tier gasoline going forward. This is easy as it is nearly ubiquitous. A quick Google search will tell you more.

SkyBox

Thanks for the info. I've always preferred Shell or sunoco, but I'll go check the official Top Tier fuel stations

Elk

Both are on the list; see, click.

Bill Dearborn

I wouldn't worry about it all that much. Top Tier doesn't necessarily mean the companies gasoline isn't any good. Some major fuel companies don't have their gasoline listed as Top Tier but still have all of the proper detergents. GM has recommended Top Tier fuel for a lot of years and when I purchased my 08 there wasn't a single top tier supplier in my area of upstate NY including some major brands. Then the companies started certifying their fuel and and suddenly there were a lot of them. Sunoco and Marathon weren't licensed until Feb. 2017. I had been filling my 2015 Z06 at the Marathon station 1 mile from my house for a year and a half before they were licensed. I know the gasoline in the station's underground tanks didn't change on the day they got the license.
https://toptiergas.com/licensed-brands/

https://en.wikipedia.org/wiki/Top_Ti...rgent_Gasoline

From that link the following statement: Gas brands can participate and get a TOP TIER license if they meet certain standards, which includes performance tests for intake valve and combustion chamber deposits, fuel injector fouling, and intake valve sticking. Additive manufacturers pay for the testing, the cost of which varies from year to year, while gasoline companies pay an annual fee based on the number of stations it operates to participate in the program.

Bill

Avanti

All my toys that spend time setting get Stabil. The C7 gets the GM stuff as the Manual recommends... can't hurt

Btw, John Deere commends fuel stabilizer for mowers and such that set around. As for octane enhancers, they shouldn't be necessary for "top-tier" premium. All the best.

Zjoe6

He said fuel treatments right? Yes top tier and octane are completely separate but both are fuel treatments and both are separately very important. Some areas don't have 93 so 91 is your only choice. If you track it or drive in hot weather octane boost is the only option.

Jason900rr

Techron

terry82

when I switched to Costco gas only, it helped to clean up the insides of the throttle bodies . I never got any pinging or knock with Costco 87 octane gas.i have used seafoam and thought it did good .but I think the Costco gas has all the cleaning stuff that I need .

us3rname

How did your gas help clean the inside of the throttle body?

terry82

costco advertises that they have a lot of detergents in there fuel.It helped to clean the inside throat of the throttle body.the injectors squirt the fuel above the throttle plate. I could tell that much difference .

Raysmuffler

Your fuel injectors are direct injected into the cylinders so fuel never touches the throttle body. So different grades of fuel can only have an effect on carbon deposits on top of the pistons and no where else. Older port injector motors could see a difference on deposits on intake valves but fuel hasn’t been injected on or around the throttle body for years.

terry82

I do not have direct fuel injection. it is a throttle body.they are set up like a carb.

eboggs_jkvl

Well, since this is a C7 forum, we assume any car listed as a topic or as a reference is a C7, thus the confusion about gasoline cleaning the throttle body. We don't even get the luxury of the gasoline cleaning the valves in this forum.

Elmer

Prime Target

Pour a bottle of Techron in the tank. I use a bottle every ~3000 miles in my cars just as preventative maintenance. Says it keeps deposits off fuel injectors. Can’t hurt.

Ken_4fun

Shell and Speedway stations in Indianapolis claim to be 93 octane. I use a mix of both.

Ken

Chazzmania

We have 92 octane here on the island and I add Boostane to my tank on every fill up. Keeps her running strong