Royal Purple 18000 Fuel Injector Cleaner - 6 fl. oz.
Best for
Best budget
Amazon rating
Amazon aggregate, one input among many in the Verdict Score
Current price
$6.48
Updated Jun 27, 2026 · 1 min read
The consensus
What reviewers found
Synthesized across the trust-weighted source mix below.
Across the reviewers we read, Royal Purple's Fuel Injector Cleaner stands out mainly on price, listing as the cheapest option in this roundup while still holding a 4.6-star average across roughly 3,400 verified-purchase ratings. For buyers prioritizing cost per bottle, that combination makes it the natural budget choice in the category. Verified-purchase reviewers generally describe it as a straightforward, inexpensive treatment for routine use, with the usual reported benefits of smoother running on engines that had existing buildup.
What reviewers liked
- Lowest price in the roundup
- Respectable 4.6-star average across ~3,400 ratings
- Inexpensive enough for routine, repeated use
- Established brand name in the additive space
Where it falls short
- Small 6-oz bottle limits per-treatment value
- Lowest average rating among the picks here
- No independent expert or lab data in our signal set
- Reported benefits depend on pre-existing deposits
Embed our score
Sell this product? Show off the rank.
Free badge for the brand, retailer, or anyone covering this product. Copy the snippet and paste it anywhere HTML works. Updates automatically when the ranking changes.
Includes a credit link back to this page. No tracking; no JavaScript.
Across the reviewers we read, Royal Purple's Fuel Injector Cleaner stands out mainly on price, listing as the cheapest option in this roundup while still holding a 4.6-star average across roughly 3,400 verified-purchase ratings. For buyers prioritizing cost per bottle, that combination makes it the natural budget choice in the category.
Verified-purchase reviewers generally describe it as a straightforward, inexpensive treatment for routine use, with the usual reported benefits of smoother running on engines that had existing buildup. The 6-oz bottle is small relative to some rivals, so per-treatment value depends on dosing and tank size. Our data contained no independent expert testing or specialist-community discussion for this listing, so the score rests on a healthy but unremarkable retailer consensus paired with its standout low price.
- Restores fuel economy
- Stabilizes ethanol
- Maximizes horsepower
- Improves responsiveness
- For use in both gasoline and diesel engines
- Fit type
- Universal Fit
If the consensus convinced you
Check current price on Amazon
Pricing and availability change frequently. Tap through to confirm before buying.