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Red Line 60103 SI-1 Complete Fuel System Cleaner, Cleans and Prevents Corrosion in Fuel Systems, Cleans Injectors, Carburetors, Valve and Combustion Chamber Deposits - 15 Ounce (2 Pack)

  • Based on 7,416 reviews
Condition: New
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Availability: In Stock.
Fulfilled by R/A Hoerr Incorporated

Arrives Wednesday, Feb 25
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Size: 15 Fl Oz (Pack of 2)


Features

  • DESIGNED TO EXCEED EXPECTATIONS: Red Line complete SI-1 fuel system cleaner treatment for cleaning and preventing corrosion in fuel systems
  • PERFORM AND PROTECT: Fuel additive cleans injectors, carburetors, valve and combustion chamber deposits with a powerful, concentrated blend of high-temp and low-temp detergents
  • EFFICIENT FUEL BURN: Gas treatment that enhances gasoline stability, while reducing the build up of gum and varnish formation
  • EASY TO USE: Use one bottle per tank for most effective treatment, additive cleans nearly 100% efficiency in one treatment
  • 15 Ounce (2 Pack)

Brand: Red Line


Item Form: Liquid


Scent: Unscented


Specific Uses For Product: Fuel System Cleaner


Material Feature: Unscented


Manufacturer: ‎Red Line


Brand: ‎Red Line


Model: ‎Fuel System Cleaner


Item Weight: ‎1.94 pounds


Package Dimensions: ‎9.41 x 5.43 x 2.52 inches


Item model number: ‎5


Is Discontinued By Manufacturer: ‎No


Manufacturer Part Number: ‎60103


Special Features: ‎Concentrated


Date First Available: September 19, 2014


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Feb 25

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Top Amazon Reviews


  • It is either this, Gumout, or Royal Purple MaxClean. These three WORK!
Size: 15 Fl Oz (Pack of 1)
I have had several cars and I have come upon Redline's reputation as perhaps THE premier maker of synthetic lubes; (*cue: AMSOIL trolls, chime in now.) After doing a lot of extensive reading about motor oil on Bob Is The Oil Guy (Google it,) I became convinced that Redline was perhaps THE best oil; and while there is no "best oil," If I was going to spend big money on oil or simply wanted the best, I would choose Redline for its proven reputation with its oils, AND HAVE REMAINED SO EVEN WITH SLIGHT FORMULATION CHANGES (Read up on API SN and how it differs from API SM and API SL, etc, there is less of what was known to be the good stuff and it has been replaced with new good stuff, /endrant) - Or, perhaps, Royal Purple for a high performance, specialty oil. Honorable mentions to Mobil 1 and Pennzoil for ultra good oils as well (do you see what I did there?) On the fence about many others; nothing "wrong" with them, but why buy Castrol... That said, this review is not about motor oil. It is about fuel system treatment. And Redline SI-1 specifically, at that! Now let me tell you why I like this Redline product... Firstly: PEA. I forget what PEA stands for, but, as far as I know, it is about the ONLY chemical or ingredient in a fuel system cleaner or injector cleaner - four categories? Well, if it goes in the fuel, then it goes where the fuel goes... So get the strongest one....... - that ACTUALLY CLEANS. Let us make a list of those that are a SHAM, and really DONT have ANYTHING of VALUE in them: - STP - Slick 50, OLD AND NEW formula.. - Lucas (there, I said it. I have some experiences as well as research with products from this company, not relevant to this review.) - Prestone - Pro-Long - SEAFOAM (!!!) - "Most of the shelf".. money-wasters.. makes Walmart happy.. -- WHY? BECAUSE THYEY DO NOT HAVE PEA, or VERY LOW AMOUNTS but more like NOT, if you look at Product Data Sheets. Labels lie. Product Material Data Sheets? They don't lie. Now, back to WHAT WORKS: I have found that there are only three, criterion: HIGH IN PEA, therefore WORKS... - Gumout with REGANE (Regane is the PEA, three GUMOUT products have it: The All-In-One, the High Mileage, and another yellow liquid version, High Mileage is Orange and All In One is amber) - Royal Purple MaxClean (** HAS PEA; just different chemicals to MAKE it PEA;) - Redline SI-1. ^^ Now.. Out of these three, Redline has the HIGHEST amount of PEA in it. Gumout has a lot, too... And I put one Royal Purple MaxClean in my car recently. I then ran out of gas. >.< Now that wasnt the Royal Purple's fault, it was my fault. THIS TIME, I will put in the Redline SI-1.. because it may work a touch better than the Royal Purple. It also costs $5 less, so, WIN! :) I can't give you MPG differences, but, cars I have used it in, that seem to run smoother EVEN WITH AS LITTLE AS 1oz. PUT IN THE GAS TANK! READ THE DOSING! -YOU ONLY NEED TO PUT IN 1 ounce or so, maybe 3oz to make you feel better but that is maybe a waste, to CLEAN THE FUEL SYSTEM-- - Cars I have used it in, partial list because I honestly do not remember all the cars: 1) 1995 Ford Taurus GL, 3.0L Vulcan, likely was a flood car, 182,000 or so miles. Could me a nice car but this one looked nice and was in good cosmetic condition with cold AC.. but was a piece of **** otherwise. Strike One for Taurus. I also had a 99 Sable that was perfect.. RAN BETTER ON FUEL SYSTEM TREATMENT OF REDLINE, JUST SMOOTHER. YOU CAN NOTICE IT IF YOU ARE TUNED TO HOW THE CARS RUNS BEFORE/AFTER WITH A TRAINED EAR AND A FEEL FOR THE CAR AND SOMETIMES TAKE NOTICE OF HOW THE CAR DRIVES WITH THE RADIO OFF AND HOW IT FEELS AND SHIFTS, PERHAPS. JUST SMOOTHER. SAME WAY WHEN YOU CHANGE OIL OR TIRES. YOU CAN TELL. *Car is gone. 2) 2000 Volvo V70 XC AWD, ~131,000, 2.4L Turbo I5 - SAME. RAN REAL NICE ON THE REDLINE IN THE TANK. *Car is gone. And no, it wasn't the fuel injectors. Made me love and appreciate Volvos and all other finer cars, this car. Or most of. Some finer cars suck lol. Something about driver error... 3) 1993 Chevrolet (get ready for it) "S10 Blazer Tahoe LT." Unknown mileage; engines switched due to issues (?) . RUNS LIKE A DREAM ON REDLINE. RUNS PRETTY GOOD ON GUMOUT TOO BUT REDLINE HAS THE EDGE. *Car is sitting, waiting for work. Going full build with it. 4) 1999 Volvo V70 XC AWD, 168,850 miles, - SAME AS THE YEAR 2000 VERSION. *The Redline is going into this car. 3oz initial treatment, though I only need to put in 1oz.. maybe I will. 5) 2003 GMC Envoy XL. 167,500 miles; 4.2I Vortec 4200. This car is abused by its mechanic, with overpriced brand new tires and 10W-40 motor oil as well as Lucas oil (straight 80 weight....... !!!!!!) when it says 5W-30 on the cap. Think about that. 5W-30 RIGHT ON THE CA.. No, er are going two or three times as thick, and calling it "better." WHAT??????????? Aint 1960 or 1970 anymore... Anyways... RUNS NICE AND SMOOTH ON THE REDLINE. NO OTHER CLEANERS USED. So, there you have it. This is why I will ONLY buy: 1) Gumout at WALMART; It costs less, and is readily available; 2) Royal Purple MaxCLEAN; This is the hardest to justify, as it costs $5 more than SI-1, has perhaps slightly not as good results, and I ran out of gas when I put it in. So I couldnt evaluate it properly.. If it runs out of gas after I put it in a half tank I am going to be a complaining consumer to the BBB but lol that wont happen... I will try that one again too, in time, with money... 3) So far, the best of the three: This Redline SI-1. ^^ This was aimed at some of the posters that leave STUPID reviews! Like "My car ran out of gas. 1 star." These are the "bad review trolls" and they need to be shot and executed by the police in the street in a public forum, like Rome and stuff. These are bad people, these trolls. They need love. And they need Jesus. But notice I am not giving a product a one-star review because I ran out of gas. Take heed, lemmings. :) And, one more thing before I hit "Submit" or "Preview my review:" PEA cleans like dishes in a dishwasher. It breaks down any dirt and stuff in fuel system, and carries it away to combustion. IT DOES NOT CLOG FUEL FILTERS. Now, sure, if your fuel filter is clogged.. Will it carry stuff from it to injectors? NO! Why? because it DISSOLVES IT. Then it goes with fuel flow. So, if using in a dirty system: USE A LOT!! USE the 3 ounces or so! GIVE IT ENOUGH TO DISSOLVE THE DEBRIS AND DIRT YOU EXPECT ARE THERE! Or, better yet, change the fuel filter. It is a little tricky and you must be careful, but on a lot of cars its easy, if its not then again: CLEANER!! :) This product will clean injectors, improve spray patterns, maybe increase VOLUME of fuel to the engine, and clean up "Ethanol poop," gas sucks nowadays, and you are a fool if you are saying that gas doesnt leave the ethanol gummy stuff in its effort to be cheapened for maximum profit, winter-blend gas (the worst,) etc. Ethanol eats rubber and isnt good for fuel systems, so why is it in gas????........... Anyways.. Cleaners DO have a purpose.. Sure, YOUR CAR WILL RUN ON JUST GASOLINE but me myself, I believe in these products that address specific things that were overlooked in the inherent design of "just normal gas delivery." Did you like or dislike my review? I tried to make minimal, or no, typos. Firefox helped by having everything underlined in red that it didnt recognize, and I scanned it twice.. Let me know! :) ... show more
Reviewed in the United States on August 18, 2013 by Joseph Corbisiero

  • Awesome stuff! Works great!
Size: 15 Fl Oz (Pack of 1)
This stuff is phenomenal! Used it in my 2014 Honda CRV with 155k miles.. brought mpg up and car is much more responsive and peppy. Will be using this and only this for my injector cleaner/carbon remover in any of my engines.
Reviewed in the United States on January 6, 2026 by Amy

  • Great product
Size: 15 Fl Oz (Pack of 2)
I did a little ‘research ’ on fuel additives and which was were best and as advertised. Red Line always came out on top. The chemicals used to clean the fuel system and top end of the engine are very effective. There are some others that are very effective but this led the group. I haven’t had the chance to compare fuel consumption yet but the pickup and idle seems to have improved. ... show more
Reviewed in the United States on January 29, 2026 by Robert Morris

  • Good cleaner that delivers noticeable results
Size: 15 Fl Oz (Pack of 2)
This fuel system cleaner pours easily and seems to help smooth out performance. It didn’t make a dramatic overnight change, but over a couple of tanks it felt like the engine was breathing cleaner and running more consistently. Value for money: Worth it for regular maintenance at this price. Ease of cleaning: Simple pour-in no mess or hassle. Works well: Helps improve throttle response and smooth idling. Leakage: No leaks or spills during use. Paint quality: N/A (no effect on paint). Protection: Feels like it supports overall fuel system health. ... show more
Reviewed in the United States on February 7, 2026 by KH

  • Great maintenance tool.
Size: 15 Fl Oz (Pack of 2)
I like to put a whole bottle of this stuff down my tank. I own a 30 year old car and it sat for 2 years before I finally decided to use it again. Basically it was running a little rough and it was sluggish at first but after consistently using this stuff for a whole month, it fixed a particular issue in my engine. Now obviously this isn't a replacement for injectors but this helps clean up a whole lot of the gunk that's inside. One thing is I didn't run the tank empty. I'm not going to do that. but what I did do,bis that before my tank was empty like maybe less than a quarter tank left, I poured a whole bottle of this stuff in then I went and filled it up. then I went over some speed bumps to kind of shake the car up a bit to make the stuff mix. listen if it works it works and it worked and now I don't have to dig inside my engine to replace my injectors. ain't no way I'm messing with those spider injectors inside of a V6 vortec 😎 ... show more
Reviewed in the United States on February 9, 2026 by Patrick S.

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