---
title: "505 Cro Engine Cleaner — $348K/yr Amazon US Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/us/automotive/505-cro-engine-cleaner"
last_updated: "2026-08-09T11:41:03.939Z"
locale: en
meta:
description: "Niche score 45/100 · $348K/yr market · 285K searches/yr · $25.41 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 45/100 · $348K/yr market · 285K searches/yr · $25.41 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "505 Cro Engine Cleaner — $348K/yr Amazon US Niche (2026) - Flapen"
---
# **505 cro engine cleaner**
**Skip it**
Strong incumbent ratings (4.7★) — this niche doesn't clear our bar today.
Market size 53Growth 25Conversion 57Competition 23Returns 97Price range 87Avg price 95Brand share 25Review moat 25Quality gap 21
**Returns**
**Incredible****0.7%**
return rate — above 5% kills the launch gate
**Avg price**
**Incredible****$25.41**
avg listing price — sweet spot $15–$100
**Price range**
**Great****$6.47–$87.87**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Conversion**
**Good****4.8%**
search→purchase rate — share of searches ending in a sale
**Market size**
**Good****$348K**
$348K/yr · 285K searches
**Growth**
**Okay****+0.1%**
90-day search growth — must beat 0% to launch
**Brand share**
**Bad****90%**
top-5 brand share — brand-locked demand
**Review moat**
**Bad****4,672.88**
avg incumbent reviews — the moat a new listing must climb
**Competition**
**Bad****72%**
top-5 click share — a locked-up shelf
**Quality gap**
**Bad****4.7★**
avg incumbent rating — lower means beatable quality
According to Flapen's Amazon United States niche tracking, 505 cro engine cleaner is a $348K/yr Amazon United States market (285K searches/yr). The top 5 brands hold 90% of demand. Verdict: Skip it — 45/100.
Data updated Jul 9, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **505 cro engine cleaner market data**
- **Units sold / yr**
- **15K–20K**
- avg 1,250–1,500/product
- **Revenue / yr**
- **$381K–$508K**
- units × avg price
- **Conversion rate**
- **4.8%**
- **Avg BSR**
- **#182**
- **Page quality**
- **0%**
- **Prime**
- **94%**
- **Sponsored**
- **71%**
- **Out of stock**
- **1.4%**
- **Avg brand age**
- **93 months**
- **Avg seller age**
- **139 days**
## **Competition & brand share**
The top 5 products capture 72% of clicks — a locked-up shelf that new listings rarely crack.
**Brands**
**10 **▲rising
**Sellers**
**88**
**Top-5 brand share**
**90%**
Top 20: 100%
**Top-5 click share**
**72%**
Top 20: 100%
**Open market**
**7%**
- Liqui Moly56% - Triax14% - MAATSEN13% - Gunk4% - Motul3% - XADO3% - Open — no brand owns it (4 brands, 7%)
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — +0.1% search growth over the last 90 days.
6K4KSpike '25Spike '26 seasonSepDecMarJunAugNovMarMay
No pronounced peak months · busiest ÷ quietest = 1.5×
[**Open Trend **](https://flapen.com/research/us/automotive/505-cro-engine-cleaner/trend)
## **Top 505 cro engine cleaner search terms**
- **engine flush**83K/yr-1.9%3.8% conv. - **liqui moly engine flush**60K/yr+10.4%3.8% conv. - **motor flush**19K/yr+10.6%3.1% conv. - **engine flush liqui moly**14K/yr+26.7%4.7% conv. - **liquid molly engine flush**13K/yr-4.5%5.6% conv. - **engine oil flush**14K/yr-11.5%4.5% conv. - **liquid moly engine flush**12K/yr-5.1%6.0% conv. - **engine oil cleaner**9K/yr-9.5%2.1% conv. - **oil flush**7K/yr+17.1%6.0% conv. - **amsoil engine flush**7K/yr-14.8%1.6% conv. [**All search terms **](https://flapen.com/research/us/automotive/505-cro-engine-cleaner/search-terms)
## **Top 505 cro engine cleaner products on Amazon**
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
0%10%$35K20%$70K30%$104K40%$139K101001K10K100K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 17 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**Liqui Moly Engine Flush Plus 300ml**Liqui Moly**$17.70**4.7★6,447 rev](https://www.amazon.com/dp/B0096Y6VBS) [2**TRIAX Pro Engine Flush Oil-Based Deep Clean Motor Oil Flush Removes Sludge & Carbon | Non-Solvent | Safe for Engine Seals Injectors | Professional Shop Grade (16 oz - 473 ml)**Triax**$13.65**4.8★234 rev](https://www.amazon.com/dp/B0FM9PZ2WT) [3**Liqui Moly motorspulung 500ML (2427) PRO LINE Engine Flush**Liqui Moly**$21.55**4.7★14,165 rev](https://www.amazon.com/dp/B001CZSG94) [4**Liquii Moly Pro-Line Engine Flush (500 ML) - 2 PACK**MAATSEN**$39.11**4.7★136 rev](https://www.amazon.com/dp/B0DF7PZ9FG) [5**Liqui Moly Pro-Line Engine Flush | 500 ml | Oil additive | SKU: 2037**Liqui Moly**$19.99**4.7★9,710 rev](https://www.amazon.com/dp/B00CR3RXTO)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**TRIAX Pro Engine Flush Oil-Based Deep Clean Motor Oil Flush Removes Sludge & Carbon | Non-Solvent | Safe for Engine Seals Injectors | Professional Shop Grade (16 oz - 473 ml)**Triax**$13.65**234 rev11mo ago](https://www.amazon.com/dp/B0FM9PZ2WT) [**Liquii Moly Pro-Line Engine Flush (500 ML) - 3 PACK**Generic**$51.03**57 rev1y ago](https://www.amazon.com/dp/B0DNTDF17Q) [**Liquii Moly Engine Flush (300 ML) - 2 PACK**MAATSEN**$35.26**12 rev1y ago](https://www.amazon.com/dp/B0DG941NK7) [**Liquii Moly Pro-Line Engine Flush (500 ML) - 2 PACK**MAATSEN**$39.11**136 rev1y ago](https://www.amazon.com/dp/B0DF7PZ9FG) [**BlueDevil Products Motor Flush - 1 Quart**BlueDevil Products**$10.39**128 rev2y ago](https://www.amazon.com/dp/B0CLYXNVP2)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**Liquii Moly Engine Flush (300 ML) - 2 PACK**MAATSEN**$35.26**4.2★**▲ 322%**](https://www.amazon.com/dp/B0DG941NK7) [**Berryman 1216 Oil Change Flush 16-Ounce**Berryman**$14.53**4.7★**▲ 88%**](https://www.amazon.com/dp/B0167O87OI) [**Liqui Moly motorspulung 500ML (2427) PRO LINE Engine Flush**Liqui Moly**$21.55**4.7★**▲ 83%**](https://www.amazon.com/dp/B001CZSG94) [**Liquii Moly Pro-Line Engine Flush (500 ML) - 2 PACK**MAATSEN**$39.11**4.7★**▲ 80%**](https://www.amazon.com/dp/B0DF7PZ9FG) [**Motul Engine Clean | Oil Additive & Flush for Gasoline & Diesel Engines | Helps Remove Sludge & Improve Oil Flow | Supports Emission System Care & Engine Protection | 300ml**Motul**$18.40**4.7★**▲ 78%**](https://www.amazon.com/dp/B019C8TGGY)
**~~View all trending →~~**
## **What buyers say about 505 cro engine cleaner**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Quality-Overall**20%
*“Excellent product”*
**Value For Money**10%
*“Good Value”*
**Fuel Efficiency**10%
*“Better gas mileage”*
**Efficiency**10%
*“Works as intended”*
**Lubrication**8%
*“Filled with Fresh oil and filter, and I also used some ProLube oil treatment, and have amazing oil pressure and have no issues anymore”*
**Noise Level**7%
*“quieter”*
**Advertised Vs Actual Product**6%
*“Product as advertised”*
**Ease Of Cleaning**5%
*“Clean and keep going”*
**Ease Of Use**4%
*“Easy to use”*
**Motor Power**4%
*“Keep that motor running”*
### **What buyers complain about **
**Noise Level**19%
*“It was very noisy lifter wise”*
**Lubrication**12%
*“Made my oil look like mud when i went to replace it”*
**Value For Money**8%
*“A little expensive”*
**Functionality-Overall**6%
*“This does not work at all”*
**Compatibility-Overall**5%
*“Did not work on my VW Tiguan”*
**Leak-Proof**4%
*“Leaking”*
**Compression**3%
*“I gained more compression on cylinders that were lacking compression”*
**Ease Of Cleaning**3%
*“It makes the oil look dirty”*
**Quality-Overall**2%
*“Bottled junk”*
**Fuel Efficiency**2%
*“expected gas milage increase”*
### **Top return reasons **
**Leak-Proof**20%
**Compatibility-Overall**20%
**Functionality-Overall**12%
**Advertised Vs Actual Product**12%
**Value For Money**11%
**Fuel Efficiency**4%
**Motor Issues**4%
**Product Condition**3%
**Defective Material/Parts**3%
**Lubrication**1%
## **Common questions**
- **Is 505 cro engine cleaner profitable to sell on Amazon United States?**
- The niche generates $348K/yr across 17 tracked products. 1 of 1 products launched in the last 360 days are still selling. 90-day search growth is +0.1%. Flapen's verdict: Skip it (45/100).
- **How competitive is the 505 cro engine cleaner niche?**
- 10 brands and 88 sellers compete. The top 5 products take 72% of clicks and top 5 brands hold 90% of demand.
- **What do buyers complain about in 505 cro engine cleaner?**
- Top complaints mined from reviews: Noise Level, Lubrication, Value For Money. The return rate is 0.7%.
- **When does demand for 505 cro engine cleaner peak?**
- Demand is steady year-round — the busiest month runs 1.5× the quietest.
- **What does it cost to enter the 505 cro engine cleaner niche?**
- Listings span $6.47–$87.87; the average listing price is $25.41 (sweet spot $15–$100). The average incumbent carries 4,673 reviews — the moat a new listing must climb.
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