Used for about 20 years - it works!
I have used ZX1 for years. I had an older Hymer Motorhome and wanted it 100% before setting off for Spain. I put this in the engine AND fuel and noticed a difference pretty soon. It seemed to be sharper off the starting-blocks, which is what you need when trying to keep up with modern traffic in a Camper. The engine seem to run a bit smoother, perhaps even more quietly - that part might be my imagination.
I have used it in EVERY car I have bought since and find similar results. Unlike another well-known engine additive, it doesn't contain PTFE which over time becomes a 'gunk.' This bonds to the metal without any residue. See the web-site for more info.
I know it's expensive compared to other products, which puts friends off buying it when I recommend it, but it does such a good job. The engine is the heart of any vehicle, once it gets into trouble or stops it is frustrating. I know when I put this stuff in the engine and fuel, that as long as I change the oil, filters etc, it will help prolong the engine and ensure it is functioning at its best.
I'm not a mechanic, but I think to myself,"As long as you do the best that you can for the engine - the longer it will last and the more efficient it will be."
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