Top Tier Gas - meets detergent standards.

[Lake X Kid]

Consumers Report article — Gas Test Findings;

For the test, an independent engine testing lab that specializes in fuel analysis operated an engine continuously for 100 hours on a cycle to represent 4,000 real miles of use. The engine was then disassembled and photographed, and its key components were weighed and measured to determine the thickness of carbon deposits. Six fuels were used, randomly selected and split among three basic gasoline sources and three Top Tier.

The results showed that on average, non-Top Tier gasoline had 19 times more carbon deposits on injectors, on intake valves, and in the combustion chamber than Top Tier gasoline.

AAA also found Top Tier gasoline can have a cleansing effect, reducing intake valve deposits by 45 to 72 percent when used over a 5,000-mile interval. Variation in the results is attributed to the detergents used by different brands.


https://www.consumerreports.org/fuel...e-a7682471234/

[Lake X Kid]

Check your local gas station pumps for this Top Tier sticker.

[doug7488]

that’s an eye opener
great info!

[Euroski]

That works well for port injected engines since injector sprays fuel on back side of valve. But with direct injection gas engines I don't see much benefit of keeping valves clean. Before retiring (2015) from VW/AUDI we still had to remove intake manifold and clean intakes valve on countless DI engines as fuel is injected into cylinder. But top-tier did keep injectors cleaner and required less replacement. I have heard some DI engines are now injecting a small amount of fuel into intake port to keep valves clean, but can't confirm. Interesting read here, one of many found with "searching"


https://team.valvoline.com/diy/truth...carbon-buildup
and

https://www.traverseforum.com/thread...raverse.22112/

[Lake X Kid]

That works well for port injected engines since injector sprays fuel on back side of valve. But with direct injection gas engines I don't see much benefit of keeping valves clean. Before retiring (2015) from VW/AUDI we still had to remove intake manifold and clean intakes valve on countless DI engines as fuel is injected into cylinder. But top-tier did keep injectors cleaner and required less replacement. I have heard some DI engines are now injecting a small amount of fuel into intake port to keep valves clean, but can't confirm. Interesting read here, one of many found with "searching"


https://team.valvoline.com/diy/truth...carbon-buildup
and

https://www.traverseforum.com/thread...raverse.22112/

My assumption (correctly or not) is that there are more Port-Injected engines, then Direct Injection on the streets, because PI is a cheaper fuel system for vehicle manufactures. Therefore, Top Tier gasoline is an important consideration when fueling your vehicle.

[turboeddie]

if you don't have this type of gas you can put a fuel addative in with the secret sauce. don't remember what it was but should be easy to find.u-tube resource.

[doug7488]

I find that most additives contain Naptha
which is about $15/gallon
was never brave enough to put it in the gas tank

[rock]

Considering the quality of Costco and the price makes them a no brainer. In my area they are about 20 cents cheaper than everyone else.

Rock

[moparbarn]

Top tier fuel being recommended & carbon deposits causing drivability & emissions issues has been a hot topic for quite some time. OBD2 brought it to the forefront with better/tighter monitoring of engine operation, in 1995 when OBD2 was phased in. Many things have been done to combat carbon deposits, from fuel quality, engineering/mechanical changes in engine design to ECU/PCM programing capabilities. One MAJOR issue is the majority of carbon deposits are formed from the unburnt fuel left in the engine at shutdown. As it evaporates at the lower temps of a nonrunning engine, it remains in the intake tract & combustion chamber. No flow, lower temps=carbon deposits. The aromatic's evaporate quickly, while the heavier stuff doesn't go away at the lower temps & turns into carbon deposits. Direct injection does help, but any valve left open is susceptible to it. Good quality fuel is in your engine's best interest, as is a good quality fuel additive. The more short trips/stopping & starting you do, the more you need an additive or even a professional induction service as part of normal maintenance. I've fought this issue as a ASE certified master tech at OEM's since it reared its ugly head. Back in the early 90's I saw cars with dead cylinders due to carbon deposits so bad the valves were not able to close! Even today, seemingly minor carbon deposits can act like a sponge (on port injected systems) causing lean surges & hesitation. On direct injected systems, they can actually disrupt intake air flow & alter/disrupt the swirl effect in the combustion chamber. I don't know all this because it's not a fairly serious problem........All IC engines are MUCH more refined today & require PROPER QUALITY maintenance to deliver both the performance & economy you pay for. JMHO from someone who has been doing this for a living for 55 or so years.

[XstreamVking]

So give the car an Italian tune up when you drive it, they need to get the combustion temps up hi to burn and blow all the nasties out.