slicky rick

With how its introduced, via intake manifold, it should work vetter than fue additives like techron...for dfi engines - vs carvon buildup on valves. But has anybody experience good bad on additives introduced through the intake manifold?

Macster

The problem with using a cleaner introduced through the intake is the variability in I guess the word is dosage.

Too little and there's no benefit. Too much and this can wash oil from the cylinder wall and possibly lead to piston/cylinder scoring.

In the worst case if too much cleaning fluid was allowed into the engine the engine could suffer hydraulic lock in one or more cylinders.

(Years ago I was taught to use water. The engine was run until hot, then the vacuum line from the intake to brake booster was removed and a line to a water supply was connected. The hose was pinched closed. The engine RPMs were raised and the pinch relaxed until some water was being pulled from the bottle or reservoir into the intake system. The engine would react: stumble/cut out; and if so the amount of water was cut back. This was kept up for a while then the hose released and the engine essentially flooded to the point it stopped running. The engine was left off a while then cranked and started and run until fully warmed up. I am sure I tried this at least once with one of my engines but I do not recall any real benefit (or harm) other than I may have changed the oil afterwards.)

Those days are long gone, thankfully. I prefer to keep the engine clean organically.

This means ensuring the oil level is not over filled, running the right oil and changing it before it gets overly contaminated with unburned fuel and water.

Keeping the plugs fresh -- which means not going overboard changing unnecessarily, but changing them only when they are due on miles (or time) -- and the air filter (stock) reasonably fresh as well. 'course, if at the time the plugs are changed if the tech believes the coils are due to change these as well.

For fuel, then, using a name brand premium grade of gasoline purchased from a busy station.

Last but not least trying to avoid using the car in a way what is conducive to engine deposit build up: short trips primarily.

If one is not able to make every trip a long one to once in a while treat the car (and one's self) to a nice long (40+ mile) drive at highway speeds.

In some cases a regular (every year?) treatment of Techron could be called for if one just can't (or won't) drive the car longer than a few miles every once in a while to let the fuel do its job and help clean the engine of any deposits.

I mean when used n the right manner the engine is self cleaning. It has to be or we would all be stalled on the road at some point with an engine too loaded up with deposits to run.

If the engine somehow develops deposits -- I have not heard from my tech sources any problems in this area with Porsche DFI engines -- there is some kind of cleaning system/setup -- developed I believe for Audi car engines but which can be suitable or adaptable for use for Porsche engines -- that involves feeding a supply of cleaning fluid to the injectors and connecting some vacuum system to the engine's intake system and positioning each cylinder in turn so the exhaust valves are closed and the intake valves are open and triggering the injector so it sprays cleaner into the chamber. This cleaner fluid and whatever it loosens is then removed by the vacuum system and this is kept up until the chamber and exposed surfaces are clean. This is repeated for every cylinder then afterwards I would think the oil should be changed.

RobC4sX51

BG 44K once a year or every 7500 miles, even on DFI engines. And ideally, w/i 1k miles before an oil change.

slicky rick

How is bg44 introduced?

RobC4sX51

Same as any other "fuel additive" but the formula is top notch. I understand the DFI intake valve not getting the full "aid"! Nada you can do about that minus the Audi (not Porsche approved) technique. The valve seats and faces will get cleaned and that is more important IMO than valve guides or intake sleeves. Order online (no affiliation).

MJBird993

My former BMW mechanic recommended Techron, but not to use it too often. Not annually, maybe every 40K miles. Of course this was before the days of DI.

I have had good experience with Seafoam, but that was on a Ford trying to fix an EGR issue. I dumped half a can in that thing, but I wasn't too concerned about blowing it up quite frankly. That would be doing me a favor.