Cactus

So I was at Pep Boys the other day and noticed all the FI cleaners and wondered how Techron became the top choice of Rennlisters everywhere?

ilko

Porsche recommends it.

Cactus

So I know it was covered before but how often should you use it and does it do anything to the plugs?

No HTwo O

I use it once a year, just prior to my yearly oil change. Changing the oil after the use of a fuel injector cleaner is the key. I learned this important step from Charles Navarro.

ironimages

Ok, so why the oil change after?

ilko

Some of the deposits that are flushed by the cleaner end up in the oil.

BobbyT

I think BMW recommends Techron also. I do the same routine as No HTwo O.

No HTwo O

I don't know exactly why, I just follow more knowledgeable peoples (Charles Navarror) recommendations. Here is a quick cut & paste from Charles' web-site:

"What fuel system cleaner, lead additive, or octane booster should I use?

Fuel system cleaners are widely available from dozens of companies, all promising everything from helping you to pass emissions testing to increasing octane. Many do little more than put a drain on your wallet. In most cases, using a quality pump premium formulation is the best thing you can do for your engine, regardless of octane requirements. Most modern engines and fuel management systems can adjust for the increased octane and provide improved fuel economy and horsepower, so even though the octane requirement may be 87 or 91 octane, it can benefit from 93 or even 94 octane.

If you want to use a fuel system cleaner, use one that meets OEM requirements and is actually used by OEMs. Redline makes a fuel system cleaner that is good for both fuel injected and carbureted engines, called SI-1. They also make a lead substitute, called just that, Lead Substitute, that also cleans your fuel system and is safe for injectors and catalytic converters. Both are excellent products ok for continuous use or occasional cleanings.

Another product endorsed by many Porsche owners is Chevron's Techron Fuel System cleaner. There are many versions of this cleaner, but it is the most expensive one (with the highest % of Technron) that does the trick. The only caveat is that many owners recommend this cleaner should be used just before you change your oil, as the fuel system cleaner can contaminate your motor oil.

Additionally, Swepco's 503 gasoline and diesel fuel improver is an excellent fuel system cleaner, but can be expensive to ship because of hazardous material charges.

Lubro-Moly also offers several professional grade fuel system products (as well as other cleaners for cooling system and engine) that are excellent.

Regardless of which you choose, I recommending using these products at least every time you change your oil (preferably before you change it!).

If you need to boost your octane, again, if you have access to race gas, that's your best bet for a guaranteed octane boost. That said, Torco makes two race gas concentrates. One is unleaded and safe for use with catalytic converters and for street use and the other is leaded (with real lead) for OFF-ROAD USE ONLY. For example, 10 gallons of pump premium blended with 1/3rd of a bottle of either concentrate yields roughly 98 octane. In my own personal testing, the engine ran smoother and the plugs were cleaner when running their race gas concentrate, as it helps the fuel burn more completely and cleaner, regardless of the fact that it did make my carbureted engine run richer. But keep in mind that lead gets into the oil and will cause accelerated wear, so try to keep lead additives or leaded fuel limited to race engines that get oil changes frequently, if not after every race."

ironimages

Thanks, that makes sense

Canyon56

A bit OT but the Narvarro quote on octane boost brings up a question for me.

Sometimes I use race gas (100 octane readily available at the pump here at some 76 stations) and sometimes I mix 91 with 100.

But I'm curious as to what octane these cars are tuned for? i.e., if I use 100 is it kind of a waste? Is it actually better performance to use a mix or just stick with 91.

I ask because my AMG's ecu will adjust the timing to the octane. But without an aftermarket tune set for a much higher octane, using 100 is a waste. The ecu sets for 91-98. There's no performance gain with pure race gas (tested on a dyno.)

What about the 993 motor? What's the "ultimate" octane in respect to performance and economy? I understand all about octane and detonation, etc., but just wonder about the ecu and timing, etc., on these cars in respect to fuel.

Cactus

So once a year sounds good to me.

Cactus

So once a year sounds good to me.

Arena993

So nice you had to say it twice

cabrio993

I use Techron once a year or every oil change. However, I'm still not convinced, nor it says anywhere on the product literature, that it can contaminate the oil if you use it any other time.

This is my thinking...If the additive is added to the gas, and if combustion happens on top of the piston, where there should be no oil on a healthy engine, any carbon deposits that could be broken lose by the techron would end up leaving through the exhaust valve.

So, unless you have a leakdown issue in your cylinder walls or your valve guides, it's hard for me to imagine the oil getting in contact with the techron or the deposits it cleans.

I still only use Techron before the oil change just in case, but I still think it's more an old wife's tale more than anything...

DCP

Octane is a rating. It is not a percentage. There are fuels with rating exceeding 100. http://en.wikipedia.org/wiki/Octane_rating