2018 test3 productsFuel & Additives
Which Fuel/engine Additive Brand Wins?
A head-to-head test of 3 fuel/engine additive options with the measured results for each. See how they ranked and watch the full test video.
Ranked first
Techron
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The measured results
Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.
| Product | Initial single-product test (dirty carburetor/badly worn engine, one tank per label directions) | Three-way carbon-prevention comparison, cylinder head area | Compression test | Three-way carbon-prevention comparison, piston and valve area | Three-way carbon-prevention comparison, overall |
|---|---|---|---|---|---|
| 1Techron | some cleaning was visible but a lot more cleaning was left to be done; narrator believes it probably takes more than the one tank the product claims is sufficient | narrator says Techron seemed to excel in this location of the engine | 101 PSI (figure from meta chapter title only, not spoken anywhere in the transcript) | not tested | not tested |
| 2Seafoam | not tested | not tested | not tested | when asked which of the three products did the best overall, narrator says Seafoam did the best in this area | not tested |
| 3Marvel Mystery Oil | not tested | not tested | not tested | not tested | narrator says it seemed to finish somewhere in the middle of the other two |
How it was tested
- single-product cleaning test: Techron run through a badly worn, dirty engine and carburetor for one tank per label directions
- three-way carbon buildup prevention comparison: Techron, Seafoam, and Marvel Mystery Oil each run individually through the same cleaned engine for one tank, then torn down and visually inspected for carbon buildup by engine region
- compression test in PSI (chapter-only data, not narrated)
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