Q – The AC system on my 1986 911 is no longer cooling and I have heard that the old R-12 Freon is very expensive and getting harder to find. I never felt that the car cooled very well to begin with and I am wondering about the cost of fixing it or updating it. Karl
A – You are correct in saying that the old R-12 is getting harder to find and expensive but don’t worry about that yet. Typically the older cars that sit around a lot tend to seep Freon. If it has been a few years, don’t be surprised if it simply needs to be topped up. My philosophy is that in the absence of gross leaks or total failure, keep the R-12.
Have the system tested for leaks and if none are found, have it evacuated and put under vacuum overnight. Usually a system is considered leak free if it holds vacuum for a half hour but on an older car, especially one that uses the expensive Freon, I like overnight better. If it holds, have it charged and leak tested again with a full charge. Now here’s the rub: If the system has not been charged (under pressure) for a long time, and then you have it charged, sometimes a full charge brings out a weakness in the seals. No one can say for sure that a system will hold a charge for any period of time but Porsche systems are usually pretty tough. Unless you have a corrosion issue or damage to one of the hoses, you can usually get a few more seasons out of it.
If you decide to upgrade to R-134 (the cheap stuff) the cooling will not be as good but in Michigan, you will still find it adequate. The cost to change it over is nominal and if you had a gross leak or component failure, I would recommend it. As another option, there are “drop in substitutes” available that cool better but they are more expensive than R-134 but once you change the car over, you have to use that brand. I have used a product called “FR12” and it works fine but I still run R-12 in my Carrera.
Now if you have a Carrera 1990 or newer, it still uses the old R-12 but in the case of these cars, I would suggest an update to R-134 since the system is better engineered and will work fine with R-134.
On the older Carreras, the system is wholly inadequate no matter what. If you want to be truly cool and you have a 70’s or early 80’s car, there are a number of well documented and expensive solutions. When properly installed (and watch out for interference between the coil and condenser in the engine compartment) R-134 can be used – MC
Q – My 2007 Carrera had a lot of brake dust on the calipers and wheels and it was ugly. I bought some wheel cleaner, sprayed it on, and now it looks like the wheels and calipers are discolored. Help. John
A – Wheel cleaners usually contain acid and you may have permanently damaged the finish. The best suggestion that I have is to remove the wheels and clean them inside and out with a PH balanced wheel cleaner (P-21S or Griots). Then apply a thick coat of “wheel wax” which is specially formulated for wheels. Your wheels are painted and clear coated so other than removing some of the clear coat, they will probably look OK. As far as the calipers, if the finish is etched by the cleaner, other than painting them, the damage is done. Incidentally, since you take the car to the track, most paints will tend to burn off so if you decide to paint them, use paint formulated for brake parts that is heat tolerant. – MC
Q – I opened the glove box on my 1986 944 and the two plastic brackets that keep it from flopping to the floor broke, one right after the other. They are part of the glove box door and when I checked on the price of a new door I practically passed out. Does anyone make a repair part for it? John
A – I like making things. And I would rather repair something than buy it new, provided it is cost effective. The solution I used on my 944 was some thin gauge aluminum cut in the pattern of the original broken part with an added flange to secure it under the inner cover of the door. With some small screws that won’t poke through the outer cover, the repair pieces can be glued in between the inner and outer parts and only you will ever know that it was ever broken. – MC
Q – My 928 hatch release is driving me crazy. Sometimes it works and sometimes not. The other thing that’s strange about the car is the window switches. They worked fine until I parked the car for a few weeks and now one works 9 times out of 10 and the other one only works if I push it down really hard. I already replaced them but I got them online, not from Porsche. Tom
A – The problems that I see most frequently on 928 electrical issues have to do with storing the car and this goes for 944, and Carrera too. The switches get oxidized and quit working. If you keep trying the switches sometimes they will miraculously start working again and the more you use them the better they will work.
I usually trust original Porsche switches but my faith was recently shaken when a brand new switch blew the fuse for the windows as soon as I plugged it in. The markings on the switches were identical for the O.E. switch and the aftermarket switch. Both were made in Hungary, by the same manufacturer, had the same markings, with only one exception. The Porsche switch was date coded. And for the extra 30%, it still blew the fuse.
As far as the hatch release, once you go through all the usually tests and adjustments, you will notice that the switch only works with the door open. I was fooled by this one and wasted some time and money (mine) researching a phantom problem. Sometimes I am better at giving advice than taking it. I should have read the book on this one. Duh! – MC
Q – My Boxster flooded and now my power locks don’t work. I sopped a half gallon or so of water from under my driver seat and I am afraid that the box under there may have gotten wet. Ed
A – In the “boot”, where the top lives when it is down, there are two drains that sometimes clog with leaves, twigs, etc. Think of them as an onboard composting pile. (Boxster owners take note) When the drains clog, the boot overflows and that is how the water got in. After you get them unplugged, the driver seat should be removed and everything dried well. As soon as an electrical component gets wet, you should disconnect the power and dry the component. If you leave them wet and powered up, they are certain to get fried in short order. –MC
Q – I was wondering about lowering my 1985 Carrera. I was told that the front torsion bars are easy to adjust and that the rear ride height is adjustable too. Is this something I can do my self?
During my investigation, I also removed the side skirts on my Carrera to clean them up and tidy up some rough spots on the body. When I turned a couple of the screws that hold them to the brackets on the right rocker panel, the whole bracket ripped off my car! The oil lines run along that side and I am wondering how I am going to replace them without removing the oil lines. This is really starting to get complicated. –Wade
A – Lowering the front end is easy and inexpensive on this generation Carrera. The rear end ought to be fairly straightforward except that I have found that the torsion bars are set from the factory, to go up, not down. Maybe they expected them to sag? That, combined with the age of the rubber bushings (that are now over twenty years old) turns this job into a nightmare. The rubber donuts act as bearings and get destroyed along with the torsion bar caps. While it is expensive, I think that most folks will not have access to the wide array of dangerous tools needed to do it safely.
As far as the side skirts, you are skewered on the horns of a dilemma. To replace those brackets, you will have to lower or remove the oil pipes, grind down (or cut) to solid metal and weld them back on. That is going to hurt.
An alternative method that I have used is rectangular plastic blocks that attach to the rocker panel with two stainless steel screws. If you engineer them well, the side skirt can be secured to them. They are every bit as solid as the original bracket. When the car does get restored in the next decade or two, you might want to put the original brackets back on but if you want to drive your car this summer, it is hard to beat plastic and stainless steel. – MC
Q – I just got my 1992 Carrera 4 out for the summer and what a surprise. The taillights on the left side don’t work and I can see water inside them. The dome light fell out and it doesn’t work. I am also getting a “light show “on my dash. Numerous warning lights are coming on at random as I drive the car. If I turn it off and then back on, they all work normally for a while. My radio is also dead. I had none of these problems when I stored it last fall. – Marc
A – Sounds like it is time to do some electrical spring cleaning. This is what makes keeping old cars such a treat. There is always something to tinker with. Isn’t it great when you can actually fix things? Got a few hours to play with your Porsche? Let’s dig in.
The taillights on this model leak water and the contacts have probably corroded on the lighting sockets or in the plugs. First remove the assemblies and drain the water. Look for some white crusty residue or red rust on the sockets or around the terminals. That shmutz is the byproduct of galvanic corrosion and it is easily brushed off to make a good contact again unless it has rotted the contacts out of the socket. If the sockets have rotted beyond cleaning, bulbs can be “hard wired” to the harness, if you prefer to spend your cash on necessities. Since the sockets are not available as a separate part this is an economical and reliable repair. Once you clean everything, apply a thin layer of silicone dielectric grease to the areas that corroded.
Of course then there’s the issue of how did the water get into the taillight if it is not broken? The lenses are heat welded to the reflector and the weld has probably failed. If you can afford it, just replace them. The problem is, the new ones won’t match the color of the others since the red tends to fade and they become pink. The other problem is the extreme cost of two new lights and the center taillight. So if you are industrious, you can try to reseal them. And if the reseal doesn’t work, I cover my bets by drilling three tiny drain holes in the bottom of the reflector so any water that gets in can also get out. If the water can’t attack the metal, the taillights should be as reliable as they were for the first 17 years.
The dome light fell out of the roof since the plastic housing has warped from age and heat. It seems to happen to all Cabrios. If it works fine otherwise, you can increase tension on the little bullet shaped pins by adding some discretely placed layers of tape. I prefer narrow strips of blue or green masking tape. Don’t use electrical tape, duct tape, or scotch tape. It tends to get gooey.
As far as the dome light not working, I bet that the rubber boots for the dome light switches are rotted. Look carefully. When water runs down the A-pillar, it seeps into the switch if the boot is torn. Once water seeps in, corrosion occurs at the contact point (which you can’t see) and the dome light switch fails to turn the light on. You can unscrew the switch, clean it with contact cleaner and a small brush then lubricate it with silicone grease. With a new boot, just like the taillights, you are good for years.
That light show on the dash can have numerous causes. When your battery goes dead, a number of things can happen if you jump the car. If the systems that are indicated actually function, worry less about the lights and take it in for a computer scan. This may reveal the source of the fault and it can also reset the computer to basic settings. On some Carreras I have found the ignition switch intermittently failing which will also cause this symptom (it is not a very expensive part.) Once your vehicle is reset / rebooted, it will begin learning your driving style to optimize fuel mixture, ignition timing, and POWER!
The radio fuse may have blown due to a power surge. If you can remove the radio, check the fuse on the back and replace it. If you can’t see it blown, that doesn’t mean that it will pass current. Check it with a meter. Once the radio powers up, if it is in “code” or “safe” mode, it will need to be reset with your security code. If you have the code but don’t know how to reset it, pay a kid to do it, they are a lot smarter than us when it comes to electronics. Ask me, I have two teenagers. –MC
Q – On my 85 Carrera it is time to replace the brake hoses and I have mixed feelings about stainless steel braided brake hoses. My mechanic recommended them but I like the feel of the original rubber hoses and I have driven cars with the aftermarket hoses. What do you think? Terry
A – Although I have my preferences, here are the facts. Both types are perfectly fine for your car and safety is not a factor when they are properly installed. The rubber sheathed hoses do have more resilience than the stainless steel. They have a small degree of softness by comparison under normal usage. On the track however, the difference may be a lot more obvious. Race cars use stainless steel for the sharper feel that they provide.
Original hoses are not expensive but they actually cost more than the stainless. So cost is not a significant factor. Installation is identical for both but here is the rub (bad pun). Rubber hoses have an abrasion resistant rubber outer layer that prevents wear from destroying the fabric inner braid that gives the hose its strength. The stainless steel hoses do not have this protective layer and when poorly installed, the stainless braid can rub through. This can lead to sudden brake failure when you need them the most. It happened to me and taught me to be very vigilant with hose installation. – MC
Q – I am excited to get my car out and blast down I-75 with my Valentine One on highway mode. I am ready but I wonder if my Carrera is. I put it away with the tires pumped up, fresh oil, etc. Anything I should do as I get it out? Pete
A – There are a few components that need special attention on a stored car: One is the battery. I talk a lot about batteries so if you find this boring, skip to the next tip. But that pesky battery sure can cause a lot of problems. It sits all winter with nothing to do, nowhere to go, no exercise and then we expect it to rise to the occasion and crank the car. It’s like running a marathon without a warm up.
Batteries contain acid. Acid can eat holes in your body (and your car’s body too). Batteries output explosive hydrogen gas. Yes, the same gas that led to the demise of the Hindenburg, another fine German machine. Why is this important? Three reasons: 1) Your battery might have gotten low on charge over the winter. 2) You might need to jump it. 3) You don’t want to blow it.
When your battery is low, follow safe jumping processes. Connect the positive cables first, then the negative cable to the dead car last. This minimizes the likelihood of a dead short that might cause sparks (or fire). Verify the positive and negative terminals and don’t simply trust the colors of the cables. I have made this mistake a couple times and it is truly thrilling! If the battery doesn’t even have enough juice to turn the car over at a normal speed, don’t jump it, charge it. And if you charge it, remember the Hindenburg. Keep sparks away. The safest method of disconnecting a battery charger is to unplug it at the outlet first, then disconnect the battery.
Tires need some annual inspection too. Don’t forget to reduce the tire pressure to summer specs. (you did keep them pumped up over the winter didn’t you?) Check the pressure and notice the deviations between where you had inflated them versus where they are now. It is significant when you notice a deviation between tires. You need to keep your eye on that. Say your right rear tire lost 10 pounds and the other three lost 5. After your run down the freeway, check them again and recheck them in a week or so. If you notice that right rear tire low again, you either have a nail in it or a rim leak.
When you take your car out on the freeway, does it shake? Perhaps it didn’t shake when you stored it, but it does now. This is not uncommon on stored cars. Some tires are notorious for flat spotting while other brands are not. So how long should it take to go away? On my car, with old, aged out rubber, it would take about two mils then it was gone. Other cars I have driven took longer and some, not all.
As you sat in your car, fantasizing about that drive, did you notice that funny odor? Every spring a half dozen or so cars arrive with nests, chewed wiring, and that disgusting smell of rodents who have desecrated your Porsche with urine and worse.
I remember that Saturday in spring. As I washed my car I realized that the trunk was not shut all the way. I didn’t think much of it. I mopped up the water around the weather stripping and figured that it needed to be cleaned as well. That night, after the wash, I was justifiably proud of my fine work and took my darling wife to dinner. Her comment? “Gee honey the car looks great but WHAT IS THAT SMELL!!
On Sunday, I took the entire trunk apart, the heater hoses, defroster parts and vacuumed the nest out of the car. Multiple doses of carpet shampoo, power washing, and Fabreze made it all fresh and clean again. I spent so many hours on it I took pictures of the inside of my naked trunk and vowed, no one will ever see it this clean again. I had proof.
The moral of the story…if you have a minor odor problem, don’t get it wet! Water re-energizes dried residue and makes it new again. It is unbelievably nasty. Lift up the carpet, look for evidence in the spare tire area, look back in the engine compartment and vacuum it all out then set aside an afternoon for the champion cleaning job.
If you have a Cabrio, there is also an issue of sticking rubber seals were the convertible top rests on the windshield frame. Over the winter, they can stick so tightly that the top is literally glued tight to the frame. The drive mechanism can become overloaded and damaged. That first time of the season, after the automatic release does its job, give the top a gentle push up to help un-stick it.
When you own a Cabrio, having operated the top a few times, you intuitively know how the mechanism normally sounds during the different modes of release, top going down, and then fully seated in the boot. If it sounds like it is laboring in any mode, STOP pushing the button and investigate. Clients sometimes do not consider the power of their own intuition, making a minor problem much worse to the power of ten. – MC
Q – My Boxster is driving me crazy. I bought it at auction for a great price but three months later, the transmission failed. I only paid 12,000 for the car but the transmission cost me another 9 grand. So I’ve got $21,000 into the car and I was OK with that until it started overheating. I have never had any problem driving it until it overheated; and even after that, the engine still runs fine.
My local mechanic replaced the water pump and the thermostat but still after a few miles, the temp gauge starts to rise and then the heater quits producing heat! I took it back and now he is telling me that he thinks the head gaskets have failed. I have read all about Boxster engine problems on the web and now I am thinking that the engine might be bad. – Brian
A – Brian you have my sympathy. I understand why you would be worried. The water pump impellers do fail. They are made of plastic! And the thermostat is a good hunch too. And although it may seem simple to replace both parts, there is an added complication that your mechanic might not have realized.
Here’s the best news. I believe that the most likely problem is that cooling system has not been properly bled. Based on Boxster cooling system design, this is not an easy task and depending on where your mechanic got his information, he might have been doomed. The factory manual is vague on the topic (presumably they handle it in on-the-car training) and we have found that the Robert Bentley manual has the most detailed written & pictorial procedure.
It’s not easy or inexpensive but getting all the bubbles out sometimes takes a couple hours, a couple spirited road tests and even after that, a pesky air bubble may rise to the top and require a coolant top up. The key ingredient is patience.
Under the plastic trim panel where you fill and check coolant and oil, there is a bleeding port which is very well hidden. Porsche does not want the car owner to ever touch it and you shouldn’t. During servicing however, if the tech doesn’t find it, it can’t be bled properly.
Another cause of coolant loss (and potential overheat) is the coolant cap itself. The original cap on the early Boxster has been superseded to a newer, better design. If you have the original cap, check the number and buy the newer version.
So before you give up on the car, take it to a qualified shop and trust the process (trust but verify…make sure they know about the bleeder port first!). Even if your mechanic thinks that the engine is damaged, you need a second opinion. Based on the last Boxster engine swap I was involved in, if it actually needs to be replaced, it will cost what the car is worth, or more! I hope that is not the case. – MC