Best carbon remover gas additive

[14.1 Grms]

What would cause the engine to run bad when it is cold / warming up?

Poor factory tuning in open-loop mode would be my guess - bad fuel trims and timing.

 

[Lubener]

What would cause the engine to run bad when it is cold / warming up?

There are not many sensors that are used in the calculation of the air/fuel ratio during open loop operation. Marginal fuel pressure can cause issues when cold where additional fuel is needed.

 

[CarGal : )]

I have a fuel injected vehicle that runs rough for about 10 minutes then all is fine. I was told I possibly have some carbon build up. Is there any new good cleaner I can put in the gas tank to address the issue?

I just bought a new Toyota RAV4 hybrid and I want it to last me long-term like 20 years so I have been doing a lot of study and research on how best to maintain my car. I have learnt everything from watching YouTube videos and doing Google research. Getting maintenance tips from professional mechanics especially Japanese and Korean mechanics - where their cars outlast cars everywhere else in the world due to their strict registration laws and their need for consistent and thorough maintenance scheduling.

This is quite a long but comprehensive answer which is aimed at giving as much education as possible to those who don’t know much about carbon buildup and car maintenance so I hope I help a lot of people with what information I have gathered to answer this question.

What year is the vehicle? What brand and type of fuel are you using? Using cheap fuel is a major cause of carbon buildup along with stop start city driving and short trips which can quickly cause carbon build up. If you don’t have much carbon buildup at the moment you may have caught it in time and you are very likely to be able to get rid of what has built up. There are a few things you can try first - after you have tried these things if you don’t notice a smoother idle, more power with acceleration and better fuel economy (your car may need a couple of treatments , maybe two or three in a row) you may instead need a professional clean, followed by carbon buildup prevention techniques.

First you need to start using a top tier fuel every time you fill up - they have added cleaning agents within the fuel to help prevent and breakdown any carbon. You may hear a lot of advice saying you don’t need to waste money on higher octane premium fuels (if your car does not particularly need it), however these higher level octane fuels contain higher levels of cleaning agents then lower octane level fuels and your cars fuel computer will get used to the change of higher octane fuel combustion. It will do your car no harm with the extra octane despite it not actually needing or using it, but it’s worth the extra few cents to use a good quality stronger cleaning agent fuel in the long-term. The extra couple of dollars per tank full will work out cheaper than professional carbon cleans in the long-term then just buying cheaper fuel. Whilst in the meantime the more expensive and better quality fuel will help your car run smoother and also help avoid other possible engine problems developing that could be more costly.

You don’t always have to use the same top tier high octane fuel brand because all brands have different types of cleaning agents in their fuels, so it is actually advantageous to rotate using a variety of different high-quality fuels so you get the benefit of all the different types of top tier engine cleaners through your fuel system.

Watch some YouTube videos on how to treat and prevent carbon buildup., videos about top tear fuels, and tips on how to maintain your car in the long-term. More frequent oil changes also have a lot to do with carbon buildup not just fuel 9 times out of 10. Maintenance needs to be done more often than manufacturers recommendations.

Choose a fuel additive with Polyetheramine (PEA), which is the most potent detergent for removing carbon, gum, and varnish deposits because it remains stable at high combustion temperatures.
Top-Rated PEA Additives:
Red Line SI-1 Complete Fuel System Cleaner: Frequently cited as having among the highest PEA concentrations on the market (~25–50%). It is favored for both deep cleaning and periodic maintenance.
BG 44K Fuel System Cleaner: Often used by professional mechanics and dealerships. It is highly concentrated; some technician tests suggest it is significantly more potent than consumer-grade alternatives.
Chevron Techron Concentrate Plus: Considered the "gold standard" and is recommended by multiple major auto manufacturers (OEMs). It typically contains 20–49% PEA.
AMSOIL P.i. Performance Improver: A high-potency cleaner specifically designed to restore fuel economy and engine performance in a single tank.
Gumout Regane High Mileage:This specific variant of Gumout is known for high PEA content compared to their standard line, making it a strong budget-friendly option.
Royal Purple Max-Clean: A 3-in-1 formula that cleans injectors, intake valves, and combustion chambers while also acting as a fuel stabilizer.
Key Usage Considerations:
Concentration Matters: Look for products specifically labeled as "Concentrate" or "Complete Fuel System Cleaner," as these typically contain higher PEA percentages than basic "Fuel Injector Cleaners". These complete fuel system system cleaners also target fuel injectors. You can even get fuel additives specifically for hybrid and diesel engines.

• GDI Engines: For modern Gasoline Direct Injection (GDI) engines, PEA is essential because carbon buildup on intake valves is more common and harder to remove.
• Application Frequency: These strong cleaners are generally recommended for use once every 3,000 to 5,000 miles (or at every oil change) rather than with every fill-up.
• Avoid "Snake Oils": Many cheaper additives rely on solvents like kerosene or alcohol, which may dislodge debris without dissolving it, potentially clogging fuel filters. Always verify the presence of PEA in the product description.

Driving Steps After Adding Fuel Additive:

Add & Mix: Pour the additive into a nearly empty tank, then fill up with a top tier fuel to mix it thoroughly. If you want a stronger clean only fill your tank halfway or three quarters full - or you can use two bottles of fuel additive, it will not harm your engine (but make sure you use an additive that also contains a lubricant as well as PEA).

Initial Gentle Drive: Drive normally or gently for a bit; some products might require idling above 2,000 RPM for a short period as they're sprayed in (for intake cleaners) or just to get them moving. Use a combination of sustained highway driving and occasional higher-RPM operation, often referred to as an "Italian tune-up".
To maximize the effectiveness of the additive follow these techniques:

Spirited Driving: Take a highway drive or find opportunities for higher RPMs (e.g., 3000-4000 RPM in lower gears) to increase engine heat and combustion intensity, helping to dissolve and burn off deposits.
Avoid Short Trips: Don't immediately go back to short commutes, as the engine needs to stay hot for the additive to work effectively.

Complete the Tank: Continue driving normally until the treated fuel is used up.
Key Principles:
Heat is Key: High RPMs and consistent driving (not just idling) generate the heat needed for cleaning.
Patience: Chemical cleaning takes time as the additive works through the fuel system and combustion chambers.
Direct Injection (GDI) Engines:These are prone to intake valve buildup; additives clean fuel injectors, but intake valve deposits might need manual cleaning.
Prioritize Highway Driving: Additives perform best during extended periods of driving at higher speeds. Longer trips allow the engine to reach and maintain its optimal operating temperature for an extended time, which is necessary to activate certain cleaning chemicals and burn off loosened carbon.
Drive up an extended mountain incline: Use ‘Sport Mode’ if your car has this driving mode as it allows maximum acceleration. Driving up an incline can keep your RPMs at a consistent and higher level for a longer period.
On the Freeway Use Higher RPMs Occasionally: Increasing engine RPMs helps the motor burn off internal carbon deposits. Brief periods of higher-RPM driving (such as during highway overtaking or a few "wide-open throttle" blasts - spirited but not too aggressive, increases airflow and treated fuel velocity through the valves, which can help dislodge deposits. When freeway driving avoid using ‘Cruise Control’ as this does not allow you to control acceleration bursts without going over the speed limit - you need to be able to gradually drop your speed back so you can accelerate and open the throttle more frequently (as long as there is no traffic behind you, which may find your varying speed annoying). Ideally you need to find a quiet time of day or night to do this kind of drive.
Maintain a Steady Engine Load: After at least an hour or two of spirited driving, drive normally and more gently for the last 10 minutes of your drive. Avoid constant idling or frequent stop-and-go city driving, which are less effective for cleaning and can actually contribute to further buildup.
If you have only done a spirited drive for an hour or two, you will still have plenty of fuel left in your tank for another spirited drive or two until your tank is running low.
Allow for "Soak Time": While highway runs are ideal for burning off carbon, some experts suggest that letting the engine sit overnight allows the cleaner to soak into and dissolve stubborn deposits on injector tips and intake valves before the next drive.
Run the Tank Low: To maximize the "contact time" and concentration of the cleaner, it is often recommended to drive until the treated tank is nearly empty (around 1/4 tank) before refilling with top tier fuel. Avoid using ‘Eco Mode’ when driving with a fuel additive as Eco Mode’ holds acceleration back.
Use a fuel additive treatment every 3,000 miles or every 3 months to prevent carbon buildup. Some fuel adjectives recommend using every 5000 miles or 8000 miles. ( I travel 10,000 Km per year and use a fuel additive every 2,500 Km’s in my RAV4 hybrid. I also do my oil change services every 5,000 km’s or 6 months: Despite TOYOTA recommending services every 15,000 Km’s or 12 months.

Severe Cases: For extreme buildup, additives might not suffice, requiring professional manual cleaning, such as all walnut blasting or other treatments.

Also don’t forget to get your automatic transmission fluid changed at 50,000 Km or 4 to 5 years, brake fluid at 20,000 Km or 2 years and coolant changed regularly at every 3 years and any other fluids that may need attention. There is also your MAF sensor. that can also have carbon buildup on it affecting the airflow which then affects your fuel ratio and a small part called the PVC valve which needs to be checked/changed every 12 months. I also get my tyres rotated and balanced every six months and wheel alignment every year. You can learn all of these basic maintenance tips and I’m sure you will learn about things that you never knew about things that can save you a lot of money. For example from watching a basic YouTube video. “20 tips to maintain your car to last 300,000 miles”.

I have built a library of YouTube videos to keep. I have drawn up an extensive maintenance schedule so I know what needs doing when and roughly how much money I will need so I have a car savings account especially for the extra maintenance that is not covered by scheduled services or by warranty; and I also keep very detailed log books and invoices for everything that I get done on my car - I even keep a fuel log with how many litres purchased, the type of fuel and how many Km’s I travel. I can drive 100 km on less than 5 L of fuel and at $1.90 a litre that is extremely economical from my 55 L tank I get over 1,100 Km’s!

Preventative maintenance costs money but it is much cheaper than paying for major catastrophic breakdowns. I know by my maintaining my car in the best way I can it will give me the longevity it is capable of providing.

I hope all this information has helped you and other readers out there.

 

[Marcozi]

I'd scan the engine computer for codes. That's the first step. The Service Engine Soon light is on only when an emissions related problem exists.
Engines run in the open loop mode for less then 30 seconds, typically. The open loop mode is used until the catalytic converter reaches a specific temperature.