--- product_id: 47954805 title: "STP GST50400EN 0.4L Complete Fuel System Cleaner 400ml Petrol Additive" brand: "stp" price: "$36.78" currency: USD in_stock: true reviews_count: 12 category: "Stp" url: https://www.desertcart.us/products/47954805-stp-gst50400en-0-4l-complete-fuel-system-cleaner-400ml-petrol store_origin: US region: United States of America --- # 400ml concentrated formula boosts engine power & efficiency cleans entire fuel system STP GST50400EN 0.4L Complete Fuel System Cleaner 400ml Petrol Additive **Brand:** stp **Price:** $36.78 **Availability:** ✅ In Stock ## Summary > ⛽ Unlock your engine’s hidden potential—because your car deserves the best! ## Quick Answers - **What is this?** STP GST50400EN 0.4L Complete Fuel System Cleaner 400ml Petrol Additive by stp - **How much does it cost?** $36.78 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/47954805-stp-gst50400en-0-4l-complete-fuel-system-cleaner-400ml-petrol) ## Best For - stp enthusiasts ## Why This Product - Trusted stp brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Long-Term Engine Health:** Regular use keeps injectors clean, ensuring smooth starts and a rough-ride-free ride. - • **Fuel Efficiency Maximized:** Optimizes fuel delivery for longer drives and fewer stops at the pump. - • **Simple, No-Fuss Application:** Just add to a full tank and let it work its magic—no mechanic needed. - • **Peak Engine Performance Restored:** Removes stubborn deposits to unleash your car’s true power. - • **Trusted by Drivers for Over a Decade:** Proven reliability with a 4.6-star rating and loyal users worldwide. ## Overview STP’s Complete Fuel System Cleaner is a 400ml concentrated liquid designed to clean and condition your vehicle’s entire fuel delivery system. Trusted for over 10 years, it removes deposits that cause rough idling and misfires, restoring engine power and improving fuel efficiency. Easy to use by adding directly to a full tank, it supports long-term engine health and consistently helps vehicles pass emissions tests. ## Description Concentrated formula cleans and conditions your car's entire fuel delivery system, removing deposits to recover peak engine performance and fuel efficiency. Review: Great product, does exactly as it says! - I've used STP products for a long time, especially the Complete Fuel System Cleaner, which I've been using for over 10 years now. I use it on my wife's car, a couple of weeks before the MOT, to ensure the engine is running smoothly and emissions are low. Its never failed an MOT on emissions ever, in the 10 years I have been using it. Very simple to use-just add it to a full tank of petrol (there is a diesel version-so make sure you buy the correct one) via the petrol tank. Easiest way is once you have taken the lid off and removed the foil cover, is to place a funnel into the petrol slot, which keeps the metal flap (which opens when you push fuel nozzle in and springs close when nozzle is removed) open, or carefully keep bottle upright until you are ready to pour in, then quickly push the narrow top of the bottle into the petrol flap, pushing the flap down as you go, this ensures all the cleaner enters the tank. If you pour slowly, you will have to wait for small amounts of the liquid to go into the tank, via the closed flap, which takes an age to do. Don't fill up the tank with petrol again, until you get onto your 'red' warning or 'low fuel' warning light/indicator comes on, this is to ensure you dont dilute the cleaner with extra petrol and give it enough time to work its way through the engine. You should notice after a few drives (once fuel has had a chance to be cleaned) that you get a bit of 'extra power' when you put the accelerator down. This does depend on how clogged your injectors were in the first place. Review: Works - Not used my car much at all during the pandemic and when starting to use it again I had rough idle, rough ride, problems starting the car and the odd misfire. I suspected dirty injector’s so put a bottle of fuel line cleaner in and also the bottle of injector cleaner and filled my fuel tank with good fuel. After a quarter of a tank, all problems where solved. Car runs smoothly, I’ve got more power and it starts everytime. I’ve filled my tank a few times since using this and the car is still working without any issues. I’ve bought some more to use again in 6 months and will continue to use for the lifetime of the car to keep it running nice. I’ll only use premium fuel from now on as well, no more rubbish from the supermarket. ## Features - Causes severe skin burns and eye damage. - Harmful to aquatic life with long lasting effects. - May be fatal if swallowed and enters airways. - May cause an allergic skin reaction. - Repeated exposure may cause skin dryness or cracking. - car parts ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00BPUYPB4 | | Best Sellers Rank | 190 in Automotive ( See Top 100 in Automotive ) 10 in Fuel Systems | | Brand Name | STP | | Contains Liquid Contents? | Yes | | Country of Origin | United Kingdom | | Customer Reviews | 4.6 4.6 out of 5 stars (768) | | Global Trade Identification Number | 05020144800866 | | Item Form | Liquid | | Item Volume | 400 Millilitres | | Item Weight | 400 Grams | | Manufacturer | STP | | Material Features | Non-Toxic | | Model Number | ST50400EN | | Number of Items | 1 | | Part Number | ST50400EN | | Scent | Unscented | | Size | 400 ml (Pack of 1) | | Special Features | Concentrated | | Specific Uses For Product | Engine | | Unit Count | 400.0 millilitre | ## Product Details - **Brand:** STP - **Item form:** Liquid - **Item volume:** 400 Millilitres - **Item weight:** 400 Grams - **Material feature:** Non-Toxic - **Number of items:** 1 - **Scent:** Unscented - **Special feature:** Concentrated - **Specific uses for product:** Engine - **Unit count:** 400.0 millilitre ## Images ![STP GST50400EN 0.4L Complete Fuel System Cleaner 400ml Petrol Additive - Image 1](https://m.media-amazon.com/images/I/616O3WaIc1L.jpg) ## Available Options This product comes in different **Style** options. ## Questions & Answers **Q: Hi, I know this has been asked already but is this safe to use on a motorbike?** A: Hi yes. I use it on my old Norton. Works wonders but don't use the whole bottle **Q: Will this restore old petroleum in my boat fuel tank** A: Don't know about boat, but my husband said it was great in the car. Hope this helps a bit **Q: Can I use both the 5 in 1 cleaner and injection cleaner in one full tank?** A: You could but I wouldn't. Both products have properties that help clean various parts from the Fuel Tank to the Combustion chamber. In fact the description of both products show 1-2 identical properties. Just use one and then the other after doing a the guide line of 3-4 thousand miles. **Q: Can this go in a 4 stroke petrol moped?** A: Yes no problem ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great product, does exactly as it says! *by C***T on 11 April 2020* I've used STP products for a long time, especially the Complete Fuel System Cleaner, which I've been using for over 10 years now. I use it on my wife's car, a couple of weeks before the MOT, to ensure the engine is running smoothly and emissions are low. Its never failed an MOT on emissions ever, in the 10 years I have been using it. Very simple to use-just add it to a full tank of petrol (there is a diesel version-so make sure you buy the correct one) via the petrol tank. Easiest way is once you have taken the lid off and removed the foil cover, is to place a funnel into the petrol slot, which keeps the metal flap (which opens when you push fuel nozzle in and springs close when nozzle is removed) open, or carefully keep bottle upright until you are ready to pour in, then quickly push the narrow top of the bottle into the petrol flap, pushing the flap down as you go, this ensures all the cleaner enters the tank. If you pour slowly, you will have to wait for small amounts of the liquid to go into the tank, via the closed flap, which takes an age to do. Don't fill up the tank with petrol again, until you get onto your 'red' warning or 'low fuel' warning light/indicator comes on, this is to ensure you dont dilute the cleaner with extra petrol and give it enough time to work its way through the engine. You should notice after a few drives (once fuel has had a chance to be cleaned) that you get a bit of 'extra power' when you put the accelerator down. This does depend on how clogged your injectors were in the first place. ### ⭐⭐⭐⭐⭐ Works *by M***. on 6 February 2022* Not used my car much at all during the pandemic and when starting to use it again I had rough idle, rough ride, problems starting the car and the odd misfire. I suspected dirty injector’s so put a bottle of fuel line cleaner in and also the bottle of injector cleaner and filled my fuel tank with good fuel. After a quarter of a tank, all problems where solved. Car runs smoothly, I’ve got more power and it starts everytime. I’ve filled my tank a few times since using this and the car is still working without any issues. I’ve bought some more to use again in 6 months and will continue to use for the lifetime of the car to keep it running nice. I’ll only use premium fuel from now on as well, no more rubbish from the supermarket. ### ⭐⭐⭐⭐ Preventative measure to reduce build-up of deposits or 'snake oil'? *by P***T on 16 February 2018* Updated review. In summary it helped low-end performance but did not improve fuel economy for same *driving style*. Do these cleaners work? This is an emotive subject but unfortunately like most people I am not trained in stripping down and rebuilding the engine in my car! So let's look at this idea about deposits another way - burning hydrocarbons makes deposits, so would you not get your home gas boiler cleaned and serviced to keep it working efficiently? I have a 2009 Kia Rio 1.4L petrol on 60k miles, the engine is a simple DOHC 16v unit with a cast iron block. I chose this product because the datasheet indicated that it is x5 more 'concentrated' than the equivalent Redex, so this was essentially the same cost versus 'cleaning power'. During the past two years I have occasionally used Redex and I am certain it has improved the engine's response and the fuel consumption, but exactly how much I don't know. The only issue I have had with this product is with dosage, the bottle label contradicts the products US website, so I used 50% bottle in 9 gallon (imp) tank. After one tankful I would say it has helped low-end performance (up to 3k rpm) but did not improve fuel economy for same *driving style*, I think the economy gain is cancelled because you inadvertently continue to use more throttle for the same rate and so use more fuel, so maybe I'll try to accelerate with less throttle and see if I get an improvement. I think next time I will try either Techron or Seafoam. At the end of the day I see this as a one-off preventative measure on a car that I put £150pcm worth of petrol into, it may be that my 10-mile commute and occasional 'Italian tune-up' are ideal in reducing the build-up of deposits. ## Frequently Bought Together - STP GST50400EN ST50400EN Complete Petrol Fuel System Cleanner, 400 ml - STP Petrol Injector Cleaner 200 ml, Mechanical Car Cleaning Products, Concentrated Cleaning Formula, Mechanical Car Cleaning Products, Made in the UK - Redex Petrol System Cleaner 250ml, Petrol Injector Cleaner To Remove Harmful Deposits, Maximise Performance & Increase Fuel Economy With Redex Fuel Additives For Petrol Engines, Suitable For Hybrids --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.us/products/47954805-stp-gst50400en-0-4l-complete-fuel-system-cleaner-400ml-petrol](https://www.desertcart.us/products/47954805-stp-gst50400en-0-4l-complete-fuel-system-cleaner-400ml-petrol) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-05-14*