C4S in Rome

I have a favor to ask. Can someone send a list of what Porsche recommends an annual service (993 of course) and what they recommend for a "major" i.e. at 30,000. If possible the intervals would also be much appreciated. I would look in my own service manual but no longer have my car so can't.

thanks,

Droops83

At my shop we like to do a "major" service every 30k miles on 993s. This involves all fluids (engine oil, gear oil, brake fluid) and all filters (both oil filters, air, fuel), and spark plugs. We also check the compression and of course give the car a thorough inspection. 993s have hydraulic lifters so no valve adjustment is needed. A minor service would be every 7500 miles since all 993s use Mobil 1 synthetic, or every year whichever comes first. We also put in Swepco 503 fuel additive at every minor service and BG 44k at every major. This stuff actually does work, never seen a regular customer car w/ clogged injectors or excessive carbon buildup. Things like belts and P/S hoses and ignition wires are done as needed. Hope this helps.

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Chris Andropoulos
Schneider Autohaus
Santa Barbara, CA

pedsurg

Chris: Could you elaborate on the swepco 503 fuel additive and bg 44k??

Thanks
Jack

Don Plumley

Chris: What is your opinion about wires, caps and rotors? SAI valve?

Droops83

Both are similar to Techron, in that they help clean out the fuel system and seem to help w/ carbon deposits in the combustion chamber. The 44k is stronger stuff, so that is why we only use it on major services vs. every oil change w/ the 503. They both seem to work well, on the cars that we regularly service, going back to 911SCs, we hardly ever see clogged up injectors or anything like that, so we don't sell the BS all-at-once injector flushes that many shops sell. This is not to say that they are miracle fluids that will make up for a lack of maintenence on a car. If you have a super high mileage car that probably will need major work soon and probably has major carbon deposits, I would not all of the sudden put a can off 44k in the tank, as that could cause that carbon to chunk off and get caught in a valve or something. Also, Chevron says they put Techron in all the gas they sell so if you use their gas it probably does the same thing, but there don't seem to be tons of Chevron stations around here; anyone know this for a fact?

The Wires, caps an rotors seem to last a long time on these cars. I would do em every 60k for preventative maintainence, but I have seen cars w/ higher mileage where they look ok. It is sometimes hard to sell wires on these cars to a customer if the car doesn't immediately need them (Ie it is misfiring because of them), since they are expensive and are more involved to install than wires on most cars. The thing you need to watch out for on these cars is the distributor drive belt. The early 964s had a problem where they would break prematurely due to ozone exposure inside the distributor. Porsche made a retrofit vent tube kit that all later 964s and all 993s have, but even w/ the vent kit, it is a rubber belt and it can break, potentially causing major damage to your engine. i would check this belt at every service and replace every 30k as a preventative measure.

As for the SAI valve, there are many, many threads on the forum that deal w/ the SAI issues, do yourself a favor and do a search, b/c although I want to help you I do not want to start another 10page SAI/CEL argument thread, here are a couple:

https://rennlist.com/forums/993-forum/294270-oh-no-not-again-sai-question.html

https://rennlist.com/forums/993-forum/289639-valve-guides-nightmare-waiting-to-happen.html

But, I will say that we have a 993 in the shop right now, it has a CEL on for 02 sensor codes (a different shop took this to mean automatically replace all 4 o2 sensors! ), but it is clearly to do w/ the SAI system, valve seems stuck and passages are probably clogged. the customer is a total cheapskate/whiner who does not like to spend money on his car, so just for fun we are gonna try a BS flush of the valve and the rest of the SAI system and see if it helps to temporarily free it up. Probably won't, but I'll keep you guys posted!

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Chris Andropoulos
Schneider Autohaus
Santa Barbara, CA

pedsurg

Thanks Chris
Jack