csertich

I think the point is that the crud you flushed our of your fuel system is now mixed in with your oil and it's good to get it out of followed by an oil change.
chuck

Ed Hughes

The "crud" will add some level of contamination to the oil. Your going through your fuel system into the combustion chamber.

No HTwo O

Dan, good question, and this one always comes up when talking about fuel system cleaners. I do it prior to an oil change, mainly for these reasons:

1) Smart people like Steve Weiner tells us to do it this way (search his old posts)

2) Smart people like Charles Navarro makes the same recommendation.

3) I am only going to use it once per year, might as well be prior to getting my oil changed.

I know very little about these cars (compared to others) but I do "know" a lot of very smart people. I just repeat what they tell me (us). We don't need to know everything, just people who do!

DanL993

OK so this presumes that the two systems are not isolated from each other and that the crud gets in the oil because the rings are not doing the job, or the stuff even gets past good rings? Do I have that right?

If that's the way is works, so be it. Otherwise, please explain further. Thanks.

IXLR8

Chuck, what "crud in our fuel system" are we talking about?

Crud in our fuel lines...injectors...intake tract? If so, that amount of crud is so negligible compared to the crud in our everyday combustion process. And if its the crud from the intake valves and combustion chamber, most of that crud will go out the exhaust tract. A before and after oil analysis would clear up that question.

Ed Hughes

As noted above, enough of the knowledgable engine guys recommend the oil change after running the cleaner through. Whether that is particulates, unburnt cleaner, or what- where is the harm in timing it thus?

dsmyth

If you don't have a direct injection(DI) engine of some sort in your vehicle( many of the newer engines) then your oil will not be be uncontaminated from a fuel service product. The active ingredients would not survive the heat of the combustion chamber and any residue left over will pass through your exhaust as Alex suggested. You can change your oil as needed before or after. I work in this field and it has been tested.

NP993

I run my car on pure Techron. No gasoline deposits in my engine.

Mike J

I like to believe Techron works, but I do not actually know, it's more on faith and perhaps advertising - on my previous 993 I had some partial blockages in my injectors, but always used Chevon fuel, BUT I did not know what the previous owners used.

Cheers,

Mike

dsmyth

Hi Mike I think you stated this once before using the analagy that its like cleaning your teeth daily and having them professionally cleaned by the dentist. I think it was you that said someting like that??
No fuel product will keep your injectors entirely clean. Much depends on your fuel quality, ethanol usage and many other factors. The quality of your fuel additive is also important as most of them just increase your octane and give you a short boost of feel good. Little or no cleaning power. Additives that are actually effective are quite expensive.

Mike J

Yeah, that was me (I think....).

Cheers,

Mike

DanL993

OK final try. Again I have no problem with the frequency, and actually believe it's a good idea, but I tend not to swallow things whole.

What are the facts that the "knowledgable (sic) people" can cite that indicate there is a contamination of the oil system resulting from use of these products and therefore the need for an oil change following their use???

Quadcammer

i think the whole thing is overrated, but I do it once a year regardless.

My 16 year old TT injectors were sent out for cleaning. They were basically perfect, and I use all different types of gas and do nothing else special

Kika

FWIW oReilly Auto Parts has Techron 2 for 1 now. I picked up 2 bottles on Saturday.

I also use it, more on faith than anything else, once a year before oil changes.

I also put Chevron gas in nearly exclusively.

berni29

Hi

I used a can of BG44K in my 993 and thought it was great. It really did clean the combustion chambers and I have no problems with my (still original) injectors.

Berni