The original discussion on Fitch was closed... which made it impossible to post an update.
The discussion doesn't show up when doing a search of forums for Fitch making it harder to link back to... but it came up in a google search.
Here's the original thread:
https://bobistheoilguy.com/forums/threads/fitch-fuel-catalyst-is-it-a-hoax.19718/page-2
After testing Fitch for ~400,000 km in a variety of vehicles we noticed that our 1.3 L 2006 Yaris showed a noticeable improvement in fuel efficiency from ~12 km/L to ~14 km/L. We added the Fitch pellets because the car was running rough, down on power and getting poor mileage (~12 km/L)... when it normally gets ~14 km/L. After application the car ran smoother, power was back up and mileage increased to ~14 km/L (normal).
We eventually tracked down the original problem to old spark plugs with a gap that was roughly twice what it should have been. It took a few thousand kilometres to work out that the plugs were at fault and replace them. The fact that the engine suddenly started running significantly better after the Fitch pellets made it harder to figure out the plugs needed replacing. However the sudden improvement proved that the Fitch pellets were responsible.
Total mileage improvement was ~10%

The discussion doesn't show up when doing a search of forums for Fitch making it harder to link back to... but it came up in a google search.
Here's the original thread:
https://bobistheoilguy.com/forums/threads/fitch-fuel-catalyst-is-it-a-hoax.19718/page-2
After testing Fitch for ~400,000 km in a variety of vehicles we noticed that our 1.3 L 2006 Yaris showed a noticeable improvement in fuel efficiency from ~12 km/L to ~14 km/L. We added the Fitch pellets because the car was running rough, down on power and getting poor mileage (~12 km/L)... when it normally gets ~14 km/L. After application the car ran smoother, power was back up and mileage increased to ~14 km/L (normal).
We eventually tracked down the original problem to old spark plugs with a gap that was roughly twice what it should have been. It took a few thousand kilometres to work out that the plugs were at fault and replace them. The fact that the engine suddenly started running significantly better after the Fitch pellets made it harder to figure out the plugs needed replacing. However the sudden improvement proved that the Fitch pellets were responsible.
Total mileage improvement was ~10%

Last edited: