924/944/968 Frequently Asked Questions

6.0 Interior/Body

6.1 My ventilation system blows hot air no matter where I set the controls

The culprit is one or more plastic bearings (clips) in the heating and ventilation mixer. Flaps in the mixer controls how much hot and cold air is blended. The broken bearings connect each flap to a servo-driven linkage.

The repair can be made working in the driver's footwell (in left-hand drive cars). The mixer is in the center console. Access to the bearings requires removing a plastic cover, located by two Philips-head screws. The cover is on the side of the center console, just behind (fore of) the console knee bolster. With the cover removed, you should see the two linkage rods, their plastic bearings, and the metal flap arms into which the clips insert. The bearings also have a metal retaining clip that locks the rod in place; it may or may not have fallen off.

If the linkage rod is still in either plastic clip, mark its depth before disassembly. If not, be sure to test the free travel of the flap arm to avoid pressure on the end stop at either limit of the servo: open or closed.

The parts you will need are:

quantity part number description
3 944.572.313.00 bearing
3 944.572.314.00 bearing
3 944.572.217.00 spring clamp

These part numbers and quantities are according to the factory fiche. You probably don't need three of each part to fix your car; these are the total quantities used in the mixer. However, the parts are cheap enough that it may be simplest to order a full complement.

This repair is also described, with pictures, in the November 2000 issue of Excellence in an article written by Gerry Burger.

6.2 Where is the %$#@!! odometer trip reset switch?

The instructions are in your owner's manual. If you don't have an owner's manual, you may want to consider purchasing one. It's chock full of handy information about your car. For the benefit of the owner's manual impaired, on the late-model cars "The trip odometer in the lower part of the speedometer can be turned back to zero by pressing the reset-button, located in the left section of the center dashboard vent. The ignition must be on." It looks like a half-sized vent air direction slider.

On the early cars, odometer is mechanical, and the trip reset button is right near the trip odometer. Caution: Do not press this unless the car is completely at rest, and not rolling, as this would most certainly cause the odometer to quit working

6.3 How do I get the sunroof off?

The owner’s manual isn’t quite complete in its description of how to remove the sunroof. The proper sequence of events for cars with an electric sunroof is:

The 924 sunroof is not motorized, and is fairly easy to remove.

6.4 My sunroof/windshield/other leaks and my car is full of water, what do I do?

There are several ways for rain to turn your car into a bathtub. Some of the more popular ones are:


There are 4 drain holes located at each corner of the channel where the sunroof sits on the roof. If they get clogged with debris it allows water to overflow into your car. Removing the sunroof and dumping some water down each hole is the best way to determine which one is causing the problem. Don't use compressed air to clean it out, it may cause the tube to detach entirely or it may fracture old and dried out plastic. Instead, try auguring out any blockage, for example with pipe cleaners or a soft wire.

Drilling holes in the firewall to run wiring

Water runs down the firewall and into your nice little hole. You may be able to seal it up, but it will probably start leaking again with the movement of the wires and vibration. Rerouting the wiring elsewhere and plugging the hole will fix your leak for good.

Rear hatch seal fails

If your rear storage compartments are filling with water, it is possible that the hatch seal has failed at the place where the hatch meets the roof.

The hatch retaining pins can also cause the hatch to leak if they are run out too far. The spoiler drains may become clogged with debris and allow water to run in over the hatch seal, so be sure to clean them out often.

Passenger footwell

The problem occurs when the battery leaks acid onto the battery tray (located directly above the passenger footwell in the engine compartment) and rusts it out. Eventually, the tray rusts completely through and allows water to enter the passenger cabin. The best way to repair this problem is to have a new piece of metal welded into place in the battery tray; however, this is expensive (around $500 ). Some have fiberglassed the tray with some success, but usually the leak will return eventually. If this has not already occurred to you, use a battery mat to absorb the battery acid and prevent the rusting. This does not apply to the newer models with the battery located in the rear.

6.5 What is the actual temperature indicated by the temperature gauge?

85.5 and previous:

85.5 to present:

6.6 I'd like to replace my hood badge, how do I get that thing off?

The hood badge has a couple of pins on the back that fit into some plastic grommets. You can use a gasket scraper or putty knife to carefully (very carefully, or your paint will be damaged) to pry off the old badge and simply push on the new one.

6.7 My hand brake won't stay up/doesn't hold the car, what's broke?

If it doesn't stay up, something is probably frozen or broken inside the hand brake assembly. You can take it apart (much easier with the driver seat out) and examine the components. Most likely the ratchet release is frozen and can be freed with some penetrating oil, or the spring is gone/broken.

The lever itself can also be the cause of the problem. The release button on the end of the lever can work its way loose, causing the lever not to engage the metal lock into place when pulled up. This button simply screws onto a metal shaft inside the lever, so screw the button back on until tight and the problem will usually be solved.

If your hand brake doesn't work well and the cable linkage looks good you may have worn out your brake shoes. Yes, the parking brake has its own little brake shoes even on cars with disk brakes all round. Typically they last a long time unless you drive around with the parking brake on. The list price is around $184 for a set of four 997-352-993-02. You can find very good used ones, since they typically don't wear very much.

The 924 with four-bolt wheel has rear drum brakes. Their shoes are engaged by both the hydraulic pedal system and by the mechanical parking brake.

6.8 My hatch is making noises, anything I can do?

Not a lot. As the ambient temperature drops, the evil things start to squeak even more. First check and make sure the hinges aren't loose or losing the hinge pins. You can alleviate some of the noises by adjusting the posts that hang down from the hatch. Hold the post and loosen the lock nut and then screw the post in a bit. Do both sides equally and try closing the hatch, repeat until it doesn't close anymore and then back off a turn.

If you're experiencing clunking, it's possible the hatch glass has separated from the frame. You can take it to a windshield shop and have them reglue the glass, it's fairly expensive but cheaper than a whole new piece of glass.

6.9 My rear hatch won't open properly

First thing to recognize is that Porsche gave up trying to make the electrical switch in the driver footwell actually open the hatch. They issued a tech bulleting saying that the switch is merely a release, unlocking the hatch, and that owner's manuals indicating otherwise were in error.

Notwithstanding this non/feature, the hatch is still something which often requires seasonal adjustment. You need to do two things: make sure the posts are adjusted to the proper length, and make sure the jaws which capture the post heads are opening and closing freely. To adjust the post height, loosen the jam nut at their base, then screw the post in or out. Try 1/4 turn increments until the length allows engagement with a little downward effort on the tail. Too long and the hatch will rattle, too short and the jaws won't engage.

To lubricate the jaws, use a penetrating/drying lubricant like Wurth HHS 2000, or simply a penetrating lubricant like WD-40. Have someone operate the electrical switch, observe the jaws, and make sure they open and close freely. They will also hang up if the two M6 flat nuts which retain the jaw to the rear bodywork are overtightened. Try adjusting these as well.

6.10 My alloys aren't very pretty anymore, anything I can do?

After several years of brake dust, harsh car wash detergents, etc., the clear coat on the alloy wheels will discolor. The best method of returning them to their proper state is to have them professionally refinished ($$$). However, you can get good results with the following procedure. Clean the wheel with a Safe For Clear coat wheel cleaner. Use a paintbrush with half of the bristles cut off to get in all the nooks and crannies (tape up the metal part, or you'll add more scratches then you remove). Rinse thoroughly and wipe down with a terry towel to make sure you get rid of the any residual dirt/brake dust. Take your favorite mild polishing compound (3M hand glaze, Meguiar's, etc.) and gently rub the discoloration or streaking out.

It's very important to protect your alloys from brake dust. Brake dust is HIGHLY corrosive and will pit and discolor your wheels. Using a quality car wax on your rims will make cleaning them much much easier and protect them from dirt and brake dust. A spray wax or general purpose wax (Pledge) is faster and more convenient but won't last as long - rewax often. Some discoloration (from heat, for example) may not clear up with the polish method, your only choices are to repaint or have them refinished professionally. The same is true if your clear coat has been scraped off or damaged. Your other option is to have them polished, or chromed. Both have disadvantages. Chrome is very delicate, especially since several intermediate layers of metal are required to bond the chrome with the wheel alloy. Polishing and clear coating gives a similar finish, and is slightly more rugged. However, when the clear-coat eventually fails the appearance of your rims will degrade rapidly. Typical pricing is $100/wheel for refinishing (painting), $110/wheel for polishing/clear-coating and $125/wheel for chroming.

6.11 I need to pull my car onto a flatbed, what do I attach the tow rope to?

There is nothing good on the front of these cars to tow by. Anything you attach that cable to (suspension arms) could cause expensive damage. If you have a 944 Turbo style nose, you can purchase a "tow eye" for a few dollars from your Porsche dealer. This is a very good item to keep in your car at all times. The part number is 996-721-151-00.

There is a point of attachment on the front end, but it is very delicate and will usually bend if the car is tightened down too much. On the outside of the frame on each side of the front end is a flat bracket with a hole cut out of it. It sticks down just in front of where the bottom skid pan bolts to the frame (the part that sticks up from the rest).

The 924 has a built-in towing hook in the front, a little to the right of the radiator.

6.12 How do I change the rear speakers?

To remove the whole panel you need to remove the quarter window and door trim, and a couple of screws. Be careful as there are push fasteners hidden like a door panel and are easy to pull out of the fiber board. Then carefully separate the material from the window and door jam and where it overlaps other panels. You have to glue it all back together and rope the widow back in. This is a horrible job and I seriously recommend avoiding it.

Yes the window has to come out, sorry. Usually the interior panel has enough extra material to go over the steel lip in the jamb and i sure that it would look like you pried it back in if you don't remove the window. I've been told since yesterday that the grill is not removable. The window comes out fairly easy. Remove the metal trim from the outside groove and then some gentle pushing will pop the rubber lip over the jamb. It is a good idea to have someone on the outside to catch if it flies out. Putting it back is a little harder. Once the panel is back in place you can secure the material back to the jamb with some trim adhesive. Be sure to let it cure fully before continuing. Then buy some nylon rope ( about 5/32, the hollow kind is best ). You wrap the rope around the window seal in the groove and place the window in the hole. have someone on the outside applying gentle pressure. From the inside pull one end of the rope to pull the lip of the seal back over the jamb. This will reseat the seal all of the way around. It is a bit of a challenge and will probably take a few tries to get it right.

Some slippery upholstery protectant like Armor-All will allow it to go in a little more smoothly but is messy and will make the upholstery a little harder to reglue if by chance you pull it loose on your first couple of tries. Feel free to post or mail me if you have any questions. As you can tell i have fought this type of project more than once. Good luck bye for now, Todd

home previous next