Fuel Additives...
 

don't abuse these. Not meant to be used every tankful, not even close. Most have high solvent naphtha agents, or similar. These can be rough on seals and polyurethane pieces inside fuel systems. Fuel additves are a supplement to clean fuel systems and upper cylinders, NOT to augment gas.

You also run the risk of abusing your catalytic converter(s), despite what it may say on the bottle.

All gas has undesireable byproducts, even the wonder gas Audi is currently pushing. These build up, it starts to become a problem. THEN you run the fuel cleaners, or on a regular but limited basis.

Good advice. Some additives are designed for continuous use at low dosage and augment the fuel.
 

There are aggressive cleaning dosages, and continuous maintenance dosages. The milder, gentler additives just take a bit longer for a full cleaning cycle of several thousand miles.

I have to say, I've never put anything in my engine or fuel on my own counsel. I retained Terry Dyson to give me the best advice possible for this engine, based on oil analysis and his professional experience. Besides doing analysis for guys like me, he consults to major and minor oil companies, automobile manufacturers, fleet operators, and racing teams.

When Terry says that Techron, FP60, FP3000 or BioPlus are additives that he recommends, I believe him, based on his experience and track record with me. He's been right on every point so far with this engine. If you read his posts on BITOG on fuel additives, he discusses some of his non-proprietary rationale for the recommendations he gives.

Those types of additives at very low dosage are already in the fuel...
 

it's still advised against, by the industry, about using fuel cleaner concentrates too much.