993 Maintenance Schedule
05-14-2006, 12:36 AM
#1
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993 Maintenance Schedule
993 Forum,
Does anyone have the scheduled maintenance list with corresponding mileage as recommended by Porsche for a 993? Even just the major maintenance schedule would be a great help.
ie - Secondary air injection ports inside the heads may be clogged and should be serviced @ 40,000 miles? Oil changes every 15,000 miles max?
Does anyone have the scheduled maintenance list with corresponding mileage as recommended by Porsche for a 993? Even just the major maintenance schedule would be a great help.
ie - Secondary air injection ports inside the heads may be clogged and should be serviced @ 40,000 miles? Oil changes every 15,000 miles max?
05-14-2006, 05:50 AM
#2
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For a PDF file of schedule maintenance email me.
Here is a list of things to look out for....
ENGINE
Secondary air injection (SAI) fault codes. This problem occurs when the SAI port becomes clogged with carbon, and the OBD II signals a fault code. While this may not affect the drivability of the car, it won’t pass smog until the fault is corrected. In about 50 percent of the cases this may require a top end rebuild. The 1995 model has OBD I, which is less sensitive to this problem. A recent thread on Rennlist discussed the purchase of a 993 from a dealer. The car subsequently failed smog, and was found to have the clogged SAI ports and a bad “check engine” light bulb—coincidence?—I think not. The “check engine” light should come on when the key is turned on prior to starting, along with all the other warning lights.
Valve guide wear. Indicators are excessive oil consumption, which Porsche defines as more than one quart per 600 miles, and oil-fouled spark plugs. The correction for this problem is a valve job, using better valve guides. Some valve guides available in the US may be superior to the ones used by the factory. One way to test for valve guide wear is to accelerate to about 6000 RPM in third gear, release the throttle, let the car coast down to about 2000 RPM, then floor the throttle. If there is significant valve guide wear, you will see lots of blue smoke from the exhaust.
Lower valve cover gasket leaks. You may not know they are leaking if you still have the lower engine tray on the car. The tray catches the oil, and until there is a huge leak, you won’t see it. The fix is to replace the gaskets. Tony, along with several other experts, recommends removing this tray. I think this tray is part of the valve guide wear problem. It holds too much heat in near the heads. To take it off, jack up the rear of the car, loosen five Dzuz fasteners with a Phillips screwdriver, and slide the tray from under the car.
Distributor caps and rotors. If you get a cylinder misfire fault code, consider replacing these, especially if there are carbon tracks inside the caps.
Vacuum distribution port. On the 993s with Varioram, this port is located in the rear of the engine bay, high on the left side. It is black rubber, with three vacuum lines coming off it, one on the end and two from the side. When it is old and tired, the vacuum can flatten it, and reduce the desired vacuum. The fix is to replace it. With all the plastic vacuum tubes on the 993, be careful not to insert them too far into the rubber fittings, or the vacuum flow can be cut off. The correct depth is 8 to 10 mm.
Drive belt tension sensor. This part can create some squeaks and squeals. To determine if it is the culprit, pull it back slightly from the belt and spin the roller. There is a DIY fix for this on www.p-car.com <http://www.p-car.com> Just remove the sensor and lube the bearing.
Alternator pulley update. This is for the outermost pulley on the alternator. The factory-installed pulley halves are thinner than the replacements. The original ones can break, and the pieces can dent the engine lid. Text from Porsche Tech Service Bulletin: When installing the new version pulley halves on the 911 Carrera and Turbo, the distance spacer is machined as part of the new version pulley and is no longer required. Because of this, it is no longer possible to store adjustment shims behind the distance spacer on the outside of the alternator pulley. Shims removed during the tensioning procedure should be stored in the vehicle tool kit.
Lower spark plug wires cracking. Probably due to excessive heat. Another reason to remove the engine tray. Cracks may be cosmetic, but if significant enough to cause misfiring, replace wires.
TURBO ENGINE
Excessive smoking on start-up. Text from Porsche TSB: When performing an oil change on the 1996 911 Turbo involving change of the oil filters, it is important to install the correct oil filter. Installation of the wrong part number small oil filter may lead to a customer complaint of engine smokes when started cold". Use the following chart as a guide for oil filter replacement.
General Information:
Vehicle type Small Filter Large filter
911 Carrera 1995 993 107 203 00 993 207 201 01
911 Turbo 1996 993 107 203 02 993 207 201 01
NOTE : Once existing stock of the small oil filter, part number 993 107 203 00 is used up, only the small oil filter, part number 993 107 203 02 will be available. The part number for the large oil filter remains unchanged.
GEARBOX/CLUTCH
Flywheel seal leaking. Replace seal.
Gearbox selector shaft leaking. Ditto. Not too difficult. Check for leaks at each service.
Slave cylinder creaking. Check for this by cycling the clutch pedal with the engine off. Fix is to remove the lubricate cylinder.
Slave cylinder hose leaking. Check on each service.
STEERING/BRAKES/SUSPENSION
Steering rack boots. Inspect on each service. Cracks in these boots allow dirt and moisture to enter, and can damage the steering rack.
Steering rack leaks. Look for power steering fluid leaks under the front of the car on each service. Also be alert for groaning or creaking noises when the steering is at extreme lock, which is an indication of low power steering fluid level.
Front brake duct modification. These ducts, hard rubber air scoops under the car, can rub and make noise at extreme lock. Tony has a modification to prevent this, which involves trimming off a corner of the duct.
Rear control-arm-mounted CV joint protection covers. At each service, check that these are in place. They protect the CV joints and boots from damage.
Shock absorbers. The OEM Monroe shocks are soft and tend to leak. Bilstein units are the preferred replacements—they are warranted for life to the original purchaser.
Suspension height. Tony recommends lowering US spec cars to the European height, which was their original design. The height was then raised to meet US bumper and headlight height specs.
Steering rack bracket. This should be added to all 993s with 18-inch wheels to stiffen the steering rack mount.
FUEL SYSTEM
Fuel cap seal. If you get a “check engine” light, one of the first things that should be looked at is the fuel cap seal to make sure it the updated one.
ELECTRICAL
AC condenser-Oil cooler fan resistors. When the engine is at full operating temperature, and the AC is on, if either fan (located in the front fenders, in front of the wheels) turns on and off at high speed, the resistor is defective. These fans should each come on at low speed first. Fix is to replace the resistor.
Alarm remote update. The “switchblade” remote can be updated to the type with a separate key and remote fob. When the alarm remote battery is failing, the range will become shorter, which indicates imminent need for replacement.
EMISSIONS
OBD II requires “trip completion” for successful smog test. Tony has the routine to accomplish this.
BODY
Headlight bulb retaining clip. This update is to correct poor bulb position caused by warpage of plastic part due to headlight heat. The update is about $6 per headlight, plus installation.
Third (center) brake light wiring through rear window. Tony has developed a fix for this that does not require window replacement.
Front bumper lower protection bar. Good idea to prevent damage to front bumper cover from bottoming out.
Outer windshield seals creaking. To eliminate creaking, drip “Pedro Ice Wax”, a bicycle chain lubricant, available at bicycle shops, around the seal. Pull the edge of the seal back to ensure getting the lube where it needs to be. If required, this seal can be replaced without removing the windshield.
Rear wing accordion torn. Inspect this seal with the rear spoiler raised. It is required for correct cooling air flow.
Noisy rear wing cable/drive mechanism. Check this by raising and lowering the spoiler with the engine off. Tony has a fix to keep water out of this mechanism. There is a DIY article on this at www.p-car.com <http://www.p-car.com>
Delaminating windshield at antenna entry. White discoloration at the lower right edge of the windshield is indicative of this problem.
Rear fender guards fading. After removing the old guards, use WD-40 to take off any adhesive residue. Apply Windex to the fender and to the new guards, fit them in place, and squeegee out any bubbles. Allow to dry.
INTERIOR
Inside temperature sensor motor. This is a tiny fan located in the dash at the climate control unit. If it is working properly, you can hear it before you start the engine. If defective, you may see fault code 45.
Cracking door pockets. Tony has developed a method to repair these using fiberglas. Much less expensive than replacing the pockets.
Here is a list of things to look out for....
ENGINE
Secondary air injection (SAI) fault codes. This problem occurs when the SAI port becomes clogged with carbon, and the OBD II signals a fault code. While this may not affect the drivability of the car, it won’t pass smog until the fault is corrected. In about 50 percent of the cases this may require a top end rebuild. The 1995 model has OBD I, which is less sensitive to this problem. A recent thread on Rennlist discussed the purchase of a 993 from a dealer. The car subsequently failed smog, and was found to have the clogged SAI ports and a bad “check engine” light bulb—coincidence?—I think not. The “check engine” light should come on when the key is turned on prior to starting, along with all the other warning lights.
Valve guide wear. Indicators are excessive oil consumption, which Porsche defines as more than one quart per 600 miles, and oil-fouled spark plugs. The correction for this problem is a valve job, using better valve guides. Some valve guides available in the US may be superior to the ones used by the factory. One way to test for valve guide wear is to accelerate to about 6000 RPM in third gear, release the throttle, let the car coast down to about 2000 RPM, then floor the throttle. If there is significant valve guide wear, you will see lots of blue smoke from the exhaust.
Lower valve cover gasket leaks. You may not know they are leaking if you still have the lower engine tray on the car. The tray catches the oil, and until there is a huge leak, you won’t see it. The fix is to replace the gaskets. Tony, along with several other experts, recommends removing this tray. I think this tray is part of the valve guide wear problem. It holds too much heat in near the heads. To take it off, jack up the rear of the car, loosen five Dzuz fasteners with a Phillips screwdriver, and slide the tray from under the car.
Distributor caps and rotors. If you get a cylinder misfire fault code, consider replacing these, especially if there are carbon tracks inside the caps.
Vacuum distribution port. On the 993s with Varioram, this port is located in the rear of the engine bay, high on the left side. It is black rubber, with three vacuum lines coming off it, one on the end and two from the side. When it is old and tired, the vacuum can flatten it, and reduce the desired vacuum. The fix is to replace it. With all the plastic vacuum tubes on the 993, be careful not to insert them too far into the rubber fittings, or the vacuum flow can be cut off. The correct depth is 8 to 10 mm.
Drive belt tension sensor. This part can create some squeaks and squeals. To determine if it is the culprit, pull it back slightly from the belt and spin the roller. There is a DIY fix for this on www.p-car.com <http://www.p-car.com> Just remove the sensor and lube the bearing.
Alternator pulley update. This is for the outermost pulley on the alternator. The factory-installed pulley halves are thinner than the replacements. The original ones can break, and the pieces can dent the engine lid. Text from Porsche Tech Service Bulletin: When installing the new version pulley halves on the 911 Carrera and Turbo, the distance spacer is machined as part of the new version pulley and is no longer required. Because of this, it is no longer possible to store adjustment shims behind the distance spacer on the outside of the alternator pulley. Shims removed during the tensioning procedure should be stored in the vehicle tool kit.
Lower spark plug wires cracking. Probably due to excessive heat. Another reason to remove the engine tray. Cracks may be cosmetic, but if significant enough to cause misfiring, replace wires.
TURBO ENGINE
Excessive smoking on start-up. Text from Porsche TSB: When performing an oil change on the 1996 911 Turbo involving change of the oil filters, it is important to install the correct oil filter. Installation of the wrong part number small oil filter may lead to a customer complaint of engine smokes when started cold". Use the following chart as a guide for oil filter replacement.
General Information:
Vehicle type Small Filter Large filter
911 Carrera 1995 993 107 203 00 993 207 201 01
911 Turbo 1996 993 107 203 02 993 207 201 01
NOTE : Once existing stock of the small oil filter, part number 993 107 203 00 is used up, only the small oil filter, part number 993 107 203 02 will be available. The part number for the large oil filter remains unchanged.
GEARBOX/CLUTCH
Flywheel seal leaking. Replace seal.
Gearbox selector shaft leaking. Ditto. Not too difficult. Check for leaks at each service.
Slave cylinder creaking. Check for this by cycling the clutch pedal with the engine off. Fix is to remove the lubricate cylinder.
Slave cylinder hose leaking. Check on each service.
STEERING/BRAKES/SUSPENSION
Steering rack boots. Inspect on each service. Cracks in these boots allow dirt and moisture to enter, and can damage the steering rack.
Steering rack leaks. Look for power steering fluid leaks under the front of the car on each service. Also be alert for groaning or creaking noises when the steering is at extreme lock, which is an indication of low power steering fluid level.
Front brake duct modification. These ducts, hard rubber air scoops under the car, can rub and make noise at extreme lock. Tony has a modification to prevent this, which involves trimming off a corner of the duct.
Rear control-arm-mounted CV joint protection covers. At each service, check that these are in place. They protect the CV joints and boots from damage.
Shock absorbers. The OEM Monroe shocks are soft and tend to leak. Bilstein units are the preferred replacements—they are warranted for life to the original purchaser.
Suspension height. Tony recommends lowering US spec cars to the European height, which was their original design. The height was then raised to meet US bumper and headlight height specs.
Steering rack bracket. This should be added to all 993s with 18-inch wheels to stiffen the steering rack mount.
FUEL SYSTEM
Fuel cap seal. If you get a “check engine” light, one of the first things that should be looked at is the fuel cap seal to make sure it the updated one.
ELECTRICAL
AC condenser-Oil cooler fan resistors. When the engine is at full operating temperature, and the AC is on, if either fan (located in the front fenders, in front of the wheels) turns on and off at high speed, the resistor is defective. These fans should each come on at low speed first. Fix is to replace the resistor.
Alarm remote update. The “switchblade” remote can be updated to the type with a separate key and remote fob. When the alarm remote battery is failing, the range will become shorter, which indicates imminent need for replacement.
EMISSIONS
OBD II requires “trip completion” for successful smog test. Tony has the routine to accomplish this.
BODY
Headlight bulb retaining clip. This update is to correct poor bulb position caused by warpage of plastic part due to headlight heat. The update is about $6 per headlight, plus installation.
Third (center) brake light wiring through rear window. Tony has developed a fix for this that does not require window replacement.
Front bumper lower protection bar. Good idea to prevent damage to front bumper cover from bottoming out.
Outer windshield seals creaking. To eliminate creaking, drip “Pedro Ice Wax”, a bicycle chain lubricant, available at bicycle shops, around the seal. Pull the edge of the seal back to ensure getting the lube where it needs to be. If required, this seal can be replaced without removing the windshield.
Rear wing accordion torn. Inspect this seal with the rear spoiler raised. It is required for correct cooling air flow.
Noisy rear wing cable/drive mechanism. Check this by raising and lowering the spoiler with the engine off. Tony has a fix to keep water out of this mechanism. There is a DIY article on this at www.p-car.com <http://www.p-car.com>
Delaminating windshield at antenna entry. White discoloration at the lower right edge of the windshield is indicative of this problem.
Rear fender guards fading. After removing the old guards, use WD-40 to take off any adhesive residue. Apply Windex to the fender and to the new guards, fit them in place, and squeegee out any bubbles. Allow to dry.
INTERIOR
Inside temperature sensor motor. This is a tiny fan located in the dash at the climate control unit. If it is working properly, you can hear it before you start the engine. If defective, you may see fault code 45.
Cracking door pockets. Tony has developed a method to repair these using fiberglas. Much less expensive than replacing the pockets.
Last edited by kkim; 05-14-2006 at 01:30 PM.
05-14-2006, 10:30 AM
#4
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Originally Posted by bfd365
993 Forum,
Does anyone have the scheduled maintenance list with corresponding mileage as recommended by Porsche for a 993? Even just the major maintenance schedule would be a great help.
ie - Secondary air injection ports inside the heads may be clogged and should be serviced @ 40,000 miles? Oil changes every 15,000 miles max?
Does anyone have the scheduled maintenance list with corresponding mileage as recommended by Porsche for a 993? Even just the major maintenance schedule would be a great help.
ie - Secondary air injection ports inside the heads may be clogged and should be serviced @ 40,000 miles? Oil changes every 15,000 miles max?
Every 15K miles/24K km:
Change engine oil
Diagnosis system: read out fault memory
Anti-pollen filter: replace filter element
Oils and fluids: visual inspection for leaks
Crankcase ventilation: check tightness of hose connections
Fuel system: visual inspection for damages, clearance and tightness of line connections
Intake air: check hoses, lines and connections for tightness
Parking brake: check free travel of parking-brake lever
Brake hoses and lines: visual inspection for clearance, damage and corrosion
Brake fluid: check level
Brake system: visual inspection of brake pads and discs to check for wear
Clutch: check play or final position of clutch pedal
Throttle linkage: check for smooth movement and full throttle opening [this one gets inspected every time the car is driven, right?]
Resonance flap and Varioram: check operation (Carrera only)
Steering gear: visual inpection of the bellows for damage
Tie rods: check play and dust caps
Power assisted steering/clutch: check fluid levels
Ball joints: visual inspection of dust caps for damage, check tightness of wheel alignment adjustment/mounting bolts
Manual transmission/axle drives: check oil level
Automatic transmission: check fluid level
Drive shafts: visual inspection of boots for leaks and damage
Exhaust system: visual instpection for leaks and damage, check tightness
Tires: check condition and correct tire pressure
Door hinges: lubricate
Door locks, hood locks and safety hook on front hood: check for tightness and operation
Safety belt: check operation and condition
Seals for doors, hood and roof: remove rubber residue from body seal contact areas, apply suitable lubricant
Vehicle lights: check operation
All headlights: check setting
Horn: check operation
Windshield washer, headlight washer: check fluid level, nozzle aim and washer fluid freeze protection level for the winter season and whcih wiper system operation
All other electrical equipment as well as indicator and warning lights: check operation
During road or dynamometer test:
Brake pedal, parking brake, clutch, automatic speed control, steering, heating, air conditioner and instruments: check operation
Oils and fluids: visual inspection for leaks
Additional service every 30K miles/48K km:
V-belt and Polyrib belt: check condition and tension
Replace spark plugs
Air filter: replace filter element
Replace both engine oil filters
Automatic transmission: change ATF and ATF filter
Drive belt for power steering pump: check condition
Additional service every 60K miles/96K km:
Manual transmission and axle drives: change oil
Automatic transmission: change oil in differential
The manual also recommends brake system and airbag system maintenance every two years. I would also change the distributor drive belt if it hasn't been replaced recently.
I, like most, do many of these activities more frequently than shown above.
05-14-2006, 01:28 PM
#6
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Originally Posted by Jascha-M
Kelly, you captured the essential BUGs (bad, ugly, good) of the 993 in few words…
Well Done!
Well Done!
