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| Porsche Dealer Offering |
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| Sleepers Speedshop Cup Holder https://sleepers-speed-shop.shoplightspeed.com/sleepers-cup-holder.html |
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| Fast-Ind two cup Offering |
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| Rennline Adjustable Seat Mounted Cup Holder |
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| CNC ALUMINUM CUP HOLDER https://www.autoatlanta.com/Cnc-Aluminum-Cup-Holder-For-Porsche-911-1965-98-Parts-PN-RAIR1.html |
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| magnetic-seat-rail style https://classicmotorshop.com/products/cupholder-porsche-modelle-1980-1996 |
Here is a good place to start for those new to a 993/964
If you are using a notebook, laptop or desktop computer:
LOOK LEFT! for a comprehensive list of topics
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Excerpt from recent thankyou notes and reviews:
A recent posting on Facebook in a Porsche 993 Group:"I’m getting blue exhaust when I start the car. My mechanic says it’s a $15 k fix."
“How full do you keep the oil tank? When I kept mine at the full level [on the dipstick] I'd go through easily a qt. per 600 miles, now I keep it at min - 1/4 [of the range on the dip stick] I use barely a qt. every 2500 miles. Even now, after spirited driving, the oil can expand to over 1/2 full [on the dash gauge].”
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| Flapper Valve Housing |
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| Filter's internal anti-drain back check valve |
If you see your oil pressure gauge regularly dip below 2 Bar at idle under normal operation consider switching to the Mobil 1-FS X2 5W-50 grade. Both of these oils have slightly higher zinc levels of 1100 parts per million which is thought to help extend the life of the valve train in our cars' engines. Other brands with similar published specifications will work just as well. Oil recommendations can be a rancorous discourse in our community, my answer to this is to each their own.I do not disconnect the rigid metal oil tube below and slightly to the rear of the smaller filter on the engine case even though it is specified in the factory procedure. My belief is that breaking the seal on the tube presents an unnecessary leak failure mode and the quantity of oil present in the lines is small. Also, others have found removing a tube that is not removed regularly can be problematic resulting in it being damaged and needing to be replaced, a real pain to do.
11. I do keep two cans of spray electronic parts cleaner on hand to clean off oil spilled on the engine, suspension, and the flapper valve & duct from removing the smaller filter.
12. When replacing the engine case and oil tank plugs I replace the crush rings and the "O" ring on the tank plug.
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| Crush Rings |
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| Oil Tank Drain Plug O-Ringg |
13.On occasion, I have reused the existing metal crush rings and heat-resistant "O" ring with no leaks. Be sure not to overtighten the tank plug, both the engine case and oil tank drain plugs are to be tightened to 50Nm (+5/-0 tolerance) or 36.9 ft-lb (+3.7/-0) according to the factory. A lifetime supply of the A22x27 aluminum crush rings and the heat-resistant 11x2.5 Viton (Fluorine rubber) green O-Rings, for the tank plug can be had on eBay or Amazon for a few dollars.
14. Button up the plastic parts, and the heating duct, mount the wheel and lightly snug the wheel nuts, then put the car back on the ground.
15. Re-torque the wheel nuts to the recommended dry thread value of 133Nm. or 98 ft./lb. (dry) in a cross-wheel star pattern sequence, then check the torque values by repeating the sequence on the now-tightened wheel nuts.
16. Refill the oil tank very slowly using a long neck funnel so the oil does not back up in the funnel or in the oil filler pipe's neck and spills out over the top and all over the place.
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| Long Neck Funnel |
17. Fill with 8 quarts +/- of oil and run the engine to a fully warmed state. This can take a 20-minute drive to achieve, looking to the temperature and oil pressure gauges to see if they have settled into their normal operating range.
18. Then, with the engine, still running, add additional oil, a few ounces at a time until oil registers on the dip-stick at approximately 1/4 of its scale with the car on level ground.
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| Dip-stick |
If you are having a shop change your oil for you:
As of late I have heard of incidents where a Porsche specialty service shop has overfilled the oil. This seems to suggest properly adjusting the oil level in a 993/964 is not universally understood even in the professional Porsche servicing community. Knowing this it may be best when having your 993's oil changed to specify that the technician only put 8 quarts in and no more. Then once you have driven your car home personally adjust the final fill level in your driveway.
If you suddenly experience what appears to be an oil leak shortly after an oil change by others here are the probable causes.
The final steps I have added with each oil change are to;
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| Fanbelt Switch |
Special considerations for the 993 Turbo Variant and smoking at startup:
Although some folks feel a little smoke at startup is a big problem, an occasional plume of smoke at startup especially if the car has been sitting for a while is normal for these cars and should be of no great concern. In any event, if the smoking still bothers you there are options to potentially minimize oil smoking at startup on the Turbo 964/993.
One theory is when at rest some oil may backflow into the turbo lubricating system and can cause a small quantity of oil to leak internally to the turbos. This oil will burn at startup making for a blue plume of smoke. Some argue that this is not plausible because at startup the turbos are cold and any oil present will not be hot enough to initially burn and cause immediate smoking. Another theory is that oil vent hoses leading from the turbo and or the oil tank to the intake discharge a small amount oil vapor that condenses on the inside of the intake manifold and this oil is immediatly injested and burns at start-up causing the plume. In any event here is what some have done to minimize smoking at startup.
- Switching to a heavier weight (20W-50W Multigrade) oil,
- Verifying the oil filters used have the internal valving to limit the back-flow such as the Porsche branded Turbo filters and;
- Making sure the oil is not overfilled (lower 1/4 of dipstick).
- There is an aftermarket oil inlet check valve
that addresses oil migration from the oil tank to the engine. There are also aftermarket check valve kits some add to the oil feed lines of the turbochargers. I hear that some adapt the 996 Turbo Oil Feed Line Check Valve 99610703079 for use on a 993 as well.
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| Relief valve locations. |
Interestingly, my car had two apparent oil leaks, one at one of the cylinder head oil return tubes. The other appeared to be on the passenger side lower valve cover dripping on the heat exchanger and smelling up the car, which I am told is a very common occurrence. I researched a DIY valve cover gasket replacement and it seemed simple enough. I went ahead and purchased the new gasket. In preparation, I cleaned the oil off the valve cover and the exhaust using a spray electronic cleaner.
Spray Electronic Cleaner
Afterward, the leak seemingly disappeared. Then I recalled that at my last oil change, I spilled a little oil when filling the engine. I wiped up most of it and hosed off the remainder I could see with the electronic parts cleaning spray. Apparently, it took weeks for unseen oil to migrate to the valve cover and ultimately onto the exhaust.
In retrospect, I wonder how many valve cover gasket or even valve cover replacements have been done on a 993 due to a botched oil change where cleaning was all that was needed. If you are experiencing a leak from what appears to be the lower right-hand valve cover just clean it off with some spray electronic cleaner first and see if it resolves the leak. Also if you are experiencing what appears to be an oil leak after a recent oil change here is a page describing the potential root causes.
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| Valve Cover Gasket |
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| Underside of the Varioram |
"I [purchased] a 97 C4S that was leaking oil (chain boxes, base gaskets, etc) after basically sitting for 18 mos (~500 miles in 2 yrs). "Drove it every day for a month and voila...all but 1 of the oil leaks stopped"
The above posting seems to suggest that just exercising an engine may cause leaks formed while standing for long periods to diminish if not resolve themselves completely
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| Filler Bellows removed |
This page contains resource notes beyond the over 100 other 993 buying, servicing, repair, and upgrade topics in this blog that just make owning, servicing, and getting parts for a 993 or 964 easier and less costly. It is a work in progress and will have entries added going forward so check back here from time to time.
CD-ROM or download .pdf Porsche Parts Catalog:
The 993 & 964 CD-ROM parts catalogs are in some respects a re-part numbered appendix to earlier model catalogs. For this reason many smaller subassembly part numbers are just plain missing. For example, the broken-out component list for the rubber shift coupler is listed in an earlier catalog with inexpensive part numbers for purchase where only the entire assembly, an expensive part is listed on the 993 CD-ROM.
Shift Coupler
Another example is the BOSCH distributor that shares many of the same parts as earlier single head designs. The drive gear, seal, and shear-pin needed to service the internal belt on a 993/964 distributor is listed for the single head BOSCH distributor in the '80s Carrera catalog these parts are most likely completely interchangeable.
Another example is the listing of electrical harness replacement plugs, sockets and other terminations most of which can be found in a setion of the 964 catalog listed at the bottom of this page. and not to be found in the 993 catalog.
The Factory 993 Parts Catalog and its earlier Model iterations can be found online with a little searching.
For example:
https://www.porsche.com/usa/accessoriesandservices/classic/genuineparts/originalpartscatalogue/
The Factory Shop Manual in binders or as a .pdf:
Similar to this the Porsche Factory Shop Manuals for the 993 & 964 act in many ways as an appendix to earlier 911 shop manuals and is missing entire subject areas covered in depth in earlier model shop manuals. For example, the sunroof mechanism design goes way back to very early cars. An early-year shop manual has a complete section on the disassembly, adjustment, servicing, and reassembly of the sunroof. This is not to be found anywhere in the newer model shop manuals. This page includes some select sections from ealier shop manuals that apply to the 993 & 964.
The factory shop manual and its earlier 911 model iterations can be found online with a little searching:
For example :https://www.carpdfmanual.com/porsche/
Items that save a lot of aggravation while owning and servicing your 993 or 964:
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The Original Equipment Emergency Jack, the jack that comes with the 993 Carrera is compact, lightweight, and extremely unsafe to use on the side of the road.
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| Original Carrera Emergency Jack |
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| Porsche Scissors Emergency Jack |
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| Generic Scissors Jack with nut, bolt & washers stud added |
With the basic reader and even if you have no intention of ever servicing your own vehicle reading out the trouble codes is as easy as using a pocket calculator and a quick Google search will tell you what the codes mean and what various folks did to clear them and the attendant Check Engine Light. This alone is very valuable for when you visit your local servicing entity you will know if the remedy they propose makes sense avoiding unnecessary work or upselling. More on this subject here.
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| Compressor Nut |
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| DME Relay |
The Specialized ECU Repair and the EZ IMMO BLOCK fobs use a modern button battery, whereas the OE fob's canister battery /contact arrangement has proven to not be perfectly reliable. I have been carrying around and using the above aftermarket fobs as daily users for several months now where they are exposed to moisture and lint in my jeans pocket and have proven to be 100% reliable to this point.
EZ IMMO BLOCK also offers a new fob that can be used to clone its configuration from any working fob. avoiding the factory programming sequence some find difficult to complete. Here is a page that discusses programming fobs, mating them to one's 993.
Porsche branded, Porsche's OE Supplier branded, and generic aftermarket branded parts:
There seems to be a lot of confusion as to the relationship of quality (durability) to a brand. For example, durability differences between Porsche branded premium priced parts versus Original Equipment manufacturer (OE) supplier branded, like BOSCH versus third party branded parts, such as URO when purchasing replacement parts for our cars.
Keep in mind the below definition of Premium Pricing as you read on:
"Premium pricing is a strategy that involves tactically pricing your company's product higher than your immediate competition. The purpose of pricing your product at a premium is to cultivate a perception in the market of your product being just that bit higher in quality than the rest."
First of all common service parts such as rotors, pads, struts, links etc were never designed or manufactured by Porsche to begin with. Their design, testing and manufacturing was left to Porsche's tier-one suppliers, Sachs, Bosch, Marinelli and others. So buying the Premium Priced product in a Porsche branded box at a 40% or more premium price vs buying it in the original manufacturer's branded box represents a poor value. Bosch makes fuel injectors, oxygen sensors and every component of the Motronic engine management system, Porsche never did.
The reason why dealers prefer to sell parts purchased through the Porsche distribution network is that they are mostly used in in-warrenty work where the published retail price is not relevant and the captive financial relationship between the dealer and the parts source is, how should I say, a lot less than arms length. Also higher Premium prices improves margins on out-of-warrenty work for customers who believe servicing should be done at a dealer.
Having higher Premium aftermarket retail parts prices is also attractive to the dealer's Independent (jobber) import car servicing customers because the higher retail price translates into higher margins when sold to you as part of a repair. In essence folks who buy parts to service their vehicles on their own (Do It Yourself) are simply not the dealer's core parts customer and for this reason dealer pricing seems, many times, to be irrationally high to the DIY folks.
It is interesting that the margines are so good on retail dealer parts and labor that an entire industry of independent service contract/extended warrenty providers has sprung up making good money by negotiating reduced pricing on dealer parts & service. These are the same folks that have your cell phone on speed-dial that are constatly phoning you about your expired new-car warrenty, go figure?
Parts sold through the dealer network or independent distributor are referred to as Service New parts. Universally, they are not subjected to the same level of quality control as the same part supplied to Porsche at car assembly. Most testing is driven by warranty periods. Many Service New parts have been through what is euphemistically called a "Quality" program to take manufacturing cost out of the part while still being durable enough to survive the reduced aftermarket warrenty period.
Aftermarket parts warranties, through the dealer or a distributor generally don't come close to those offered with the car when it was new so many of the now down graded parts simply don't last as long. This is especially true when a part has long been absent from a current production vehicle, in many cases its manufacturing has been handed off to a lower-cost, low volume manufacturer as most parts on a 993 or 964 now are. In a way, there is a perverse incentive in the entire aftermarket parts industry to make Service New parts less durable resulting in the opertunity to sell them to you more than once.
Porsche sources its aftermarket Service New dealer parts from the same manufacturers used by independent import parts distributors, referred to in the industry as Warehouse Distributors. So the same part, of the same quality in most cases, came off the same assembly line with the same quality controls regardless of who's box it is in. This is particulary true for parts where the current manufacturer originaly supplied the part to Porsche at assembly.
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| Porsche branded vs original manufacturer branded tie rod end |
Certain parts are an exception to this rule.
Performance Market parts:
Those supplied by by botique high performance parts distributors, for examle some of the items offered by StopTech who cater to those who race their cars or like the idea of installing race inspired parts on their car. They are usually limited to wheel end and suspension components and clutch & engine enhancements. These parts usually include cosmetic or functional enhancements and can have durability the same as or even better than run of the mill Service New part.
Low-Value, Low-Tech parts:
Some parts are manufactured by multiple entities under differing conditions at times using different designs of varying quality/(durability). They are usually low value. low-tech, easy to manufacture higher volume parts.
For example, the window switches in a 993/964 if manufactured in Germany or Eastern Europe are similar in design to the original factory-supplied part. The same part purchased under the URO brand and now even the Porsche branded part manufactured in Taiwan, although they look very similar, are an entirely different design internally and suffers functionalproblems that become apparent when attached in series to a second switch as is done for the passenger side window with switches on each door. So, for small incidental parts be observant of the manufacturer as printed on the actual part and/or its country of origin unrelated to what branded box it came in. The original switches supplied with our cars typically last 15 years or more and for the DIY inclined can actually be repaired and stored in one of the car's door pockets for emergency use.
As an experiment I recently researched where 993 Porsche branded verses manufacturer branded windshield glass comes from for a 993.
It turns out this is easy to do because to be sold in the US automotive glass must be labeled with a US DOT number that identifies the specific factory of origin and also the country of origin. Turns out Porsche branded glass with the Triangle-P logo comes from the same two factories in Germany as all aftermarket windshields for our cars. The only difference is the added Porsche branded logo on the Porsche dealer sold glass. So any premium price one pays for the dealer part is purely to get the logo.
Hunting for the best value in Service New replacement parts:
Many times a part will seem to be a "Dealer Only" part because the original manufacturer's part number is difficult to obtain. Many online auto parts distributors list multiple part number cross-references for a part that can be looked up and may result in a less expensive source of supply. Also, many times the original manufacturer's part number is actually printed on the part and when searching for a part using that number may result in a significantly lower cost source of supply.
For example;
The Denso supplied sensor blower part on the back of the
Climate Control Unit (CCU) discussed in the "What is that buzzing behind the dash?" section on this page. When looking at the part the original manufacturers part number is printed right on it. Where conducting an internet search under the Denso "173000" and excluding the car make extension -0410 it turns up several inexpensive alternative automotive branded part numbers in the $50-$75 range versus the Porsche dealer part that is several hundred dollars. The alternate part number may come with a different mounting frame however the frame and, if needed, the electricl plug can be harvested from your original unit.
Another example is when a part is only available at a lower price through a dealer,
just not a Porsche dealer. For example the vacuum actuators on the Varioram intake manifold, Porsche part number is 99311046202 discussed on this page. On the part is printed the supplier Pierberg's part number 7.14242.07, see the picture to the right. This number crosses to the BMW part number 11617786961. This part if purchased under the Porsche part number is $103 under the BMW part number it is $46. There are three of these on the Varioram manifold so the savings adds up rather quickly. This cross was discoverd by reading the manufactuer's part number offthe part in a picture at a distributor's web site and then searchingfor a cross on an internet distributor's part number lookup.
Remanufactured Parts:
Remanufactured parts such as alternators, starters & calipers are highly variable in the quality (durability) of the finished product. First of all the condition of the used part from which the rebuilt part is finished out has a big impact on part quality. The used part is referred to as a "core" in the industry and the remanufacturer really has no control over the condition of the cores he receives.
Each remanufacturer has their own standards for an acceptable core. In all cases, the standards doesn't in any way approach that of the new part when it was installed on your car at assembly. This is why some reman calipers exhibit loose bleeder screw casting threads that strip right out of the box. Also, a reman core may have been installed, used, and through the remanufacturing process more than once due to some unidentified failing. A failing you are now installing on your car.
Once a core is in hand the remanufacturer decides what testing is done, what parts are replaced or reused. This also explains the wide variability of durability and short warranty on these parts. Reman alternators due to their complexity are an example where durability varies widely even from the same rebuilder.
The best way to get a reman part with potentially better durability is to always remove the part from your car and have that specific part rebuilt versus one purchased on-exchange made from the cores the rebuilder has on hand. This is extremely important on parts where the supplier has a very limited source of good quality cores or the core is a precision or a complex part to begin with. It also may minimize the risk of installing of a reman part that is not configured exactly as the originally installed part. See this page for how this can be an issue.
In our cars the big one is the steering rack where rebuilder core availability is very low, core quality is just plain bad and the one recently taken from service from your car is the best bet for a durable remanufactured part hands down. Also when working with a rebuilder directly you can discuss the rebuilding process and what sub assembly parts you require to be refreshed. This is very important in the case of alternators. Luckily there usually is an electric motor/alternator/starter rebuilder with knowlegable service counter men in most cities of any size to do the work on your original component. If you have the interest here is a DIY on how to remove and reinstall a 993 steering rack.
Here is a page that lists my favorite go-to pages for parts for my 993 and also for a 964 information and parts supply.
The difference between 964 and early 993 1994-1995 Non-Varioram OBD-1 vs. and a 1996-1998 Varioram OBD-2 Carrera
OBD-I vs OBD-II
The 1995 and early 993 and the 964 OBD-I cars have a single oxygen sensor located before the catalytic converter (CAT) that is used to evaluate and adjust the engine to optimize performance while minimizing emissions. It captures data only on the exhaust emanating from the engine that can trigger a Check Engine Light (CEL), not the downstream emission components. Since it has only one oxygen sensor before the CAT it does not evaluate the effectiveness of either cylinder bank of the engine individually or downstream components such as the catalytic converters nor does it evaluate the performance of the Supplemental Air Injection system (SAI) at start-up. For these reasons, it reports fewer issues that will trigger a CEL and so will have fewer issues that will cause it to fail a state emission inspection. To identify a car as an OBD-I vehicle look under the rear bumper at the rear center of the engine one will see a single oxygen sensor screwed into the catalytic converter hanging down in a protective shroud as seen below.
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| Location of the oxygen sensor on an OBD-1 equipped car. |
The 1996 and newer 993 OBD-II car has four oxygen sensors located before and after each catalytic converter segment these are used to evaluate and optimize the performance of the engine, the catalytic converter (CAT), and the air injection system. Since it has two before CAT and two after CAT oxygen sensors it evaluates the performance of the catalytic converters as free-standing devices and the performance of the supplemental air injection system at start-up. For these reasons it reports a greater number of issues that will trigger a CEL and so more issues that will cause it to fail a state emissions inspection in most states.
The key service issue with the later 993 is that the emission OBD monitoring system will capture:
Although the prevalence and to the extent each contributes to the issue is still open to debate generally, once the ports are cleared and the check valve replaced this cause of a CEL seems to not return.
Here is a little more information on the subject of the Air Injector system's known issues including the above: Emission Control Systems - The Horror of the Check Engine Light!
964 & 1994-1995 993 Non-Varioram vs. 1996-1998 Varioram
To be clear owners of the earlier non-Varioram and owners of Varioram cars are generally happy with the performance of their vehicles. The Varioram cars breathe a little easier. The theory, I understand, is much like the valves on a trumpet where changing the air path lengths changes the frequency at which the instrument wants to oscillate. The Variorum system changes the effective length of the intake manifold runners so the air intake pulses maximize cylinder intake air charging at specific RPM ranges. This in conjunction with the larger intake valves produces slightly higher torque and horsepower at certain points along the rpm range. The varioram car is identified by a large bright cast metal intake manifold sitting over the top of the engine, see below.
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| Location of the Varioram intake manifold on cars so equipped. |
The Varioram concept was originally implemented for the 993 in the Carrera RS as a way of increasing performance and was later added to the standard normally aspirated engine. The performance enhancement is small and incremental. On the negative side, there are more vacuum actuators on the engine to actuate the valves in the intake manifold and by now they are all suspect and should be tested for leaks in their internal diaphragms, The testing procedure is in the middle of this page.
Model Year and DME differences, my understanding is that:
In any event, save all the original exhaust parts as when the car is sold finding replacement parts to put back may be problematic and expensive. In the case of the stock CAT the value of the internal Platinum/Pladium catalyst compounds have skyrocketed as of late and the used converters in older cars such as ours contain a lot of it where the street value for the internal catayst alone is aproaching $1000. For this reason , I suspect a lot of the take-off ones will be chopped up for their content. This may, in a few years, make finding a good functional used one at a reasonable price a problem.
Another is swapping out the cast suspension arms for adjustable race arms such as those sold by Tarett and others. Again these features being easily adjusted for race applications also make them easy to go out of adjustment for street applications.
Finally replacing rubber suspension components for harder resin or metal such as bushings and strut hats. These transmit noise and vibration to the car and in some cases have been implicated in sudden glass failure when used on a street-driven car. If your car is being developed as a track weapon, go for it, otherwise, I would shy away from these sorts of upgrades.
A taller tire in conjunction with a smaller diameter wheel gives you some tire tread roll-over feel as you get near the edge of the tires' grip in aggressive turningwhile driving. Roll-over is a feeling in the steering as the front tires begin to displace horizontally and the edge of the tires begins to distort or roll-over. In my experience the 18" low profile tire gives almost no warning before letting go and sliding, 19" probably no warning at all. For nonprofessional drivers, the margin of safety given by the roll-over tread steering feedback provided by smaller rims with higher profile tires before sliding is a welcome and significant safety communication.
16" vs, 18" Wheel
Finally if one peruses the catalog of documents in this blog via the list found in the top left-hand column of this document (when viewed on a desktop or laptop computer) it will provide somewhat comprehensive education on the workings, servicing, and upgrading of a Porsche 993 and many subjects that also apply to the 964.
If you found this page informative return to the main page and bookmark it for future 993-related servicing, repair, and upgrading guidance & information. If it saved you some coin consider a donation through the button on the top left margin of this page.
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#993 Upgrade
