: Fuel Additives

01-20-04, 09:18 PM
Should I put a fuel additive in my N*? Ihave heard people both for and aginst it. In my old Park Ave, I put a really good one in (can't remember the name) and it was like driving a different car by my next fill up. I know the 3800 and the N* are from two different worlds though. So whats the word?

Anthony Cipriano
01-20-04, 10:11 PM
Personally, I would avoid any fuel additives. The strong solvents in fuel additives can eat the insulation off of the windings of the fuel pump and the injector coils inside the injectors. There's no way to predict which additives have any particular solvent so the only safe way is to avoid them.

Many years ago when port fuel injection started to see high penetration in the market place the fuels of the day didn't have the correct detergents or additives in them to avoid injector deposits and intake valve deposits, both of which caused driveability problems in the late 80's and early 90's in many different brands of automobiles. Gas additives and injector cleaners became common in those years as they did clean out the deposits and cause an immediate improvement in driveability. The number of fuel pumps and injectors that they took out due to dissolving the insulation off the windings inside was not considered but it was significant.

Today, any and all major brands of gasoline have the correct solvents and detergents in them in the correct ratios to avoid the problem of deposit buildup. In addition, injector design has improved considerably eliminating the major propensity to form deposits and the negative driveability results when deposits do form.

All-in-all there's absolutely no need to add gas treatments or injector cleaners to your fuel on a regular basis. If there's some driveability problem that you consider to be due to deposit buildup there might be a case to use a solvent but that would be a random and rare case in my experience. If there's no driveability problem then there's absolutely no need or compelling reason to add anything to your fuel. It's not a proactive maintenance item nor something you need to do to keep the engine running correctly.

If you do feel compelled to put an additive in the fuel put it in the tank at the gas station, at the pump, with the engine off. Fill the tank before restarting after the additive is in the tank. I've seen several cases where individuals were headed to the station and put the whole bottle of addtive or gas treatment in the near empty tank and drove to fill up the tank. On the 2 mile drive to the station the strong, undiluted solvents destroyed the fuel pump. Put the additive in and fill the tank with the engine off so that the solvent is properly diluted and follow the manugfacturers recommendations for concentration. More is not better.

I cannot stress enough how many fuel pumps, sending units, fuel pressure regulators, injectors, etcetera have been damaged by strong solvents put in the fuel with the best intentions.

The only single gas "additive" that I routinely use and recommend is isopropyl alcohol to remove moisture from the fuel in the winter time. Isopropyl alcohol is very effecitve as a gas line "anti-freeze" and will eliminate moisture from the fuel system and will not harm fuel system components. It's not a solvent or cleaner but will help with any moisture content in the fuel/tank potentially freezing.