My 2003 Turbo has a problem at 80 miles per hour and the shop I have taken it to can not figure it out. They installed new tires and balanced them twice but still it shakes. I only have about 23,000 miles on it. I hope the suspension isn’t bent – David
A – I am happy to help, I see this all the time. First of all, to really experience this problem, the shop would have to DRIVE your car at 80 mph. That’s pretty tough around here but how else can you experience the problem. I’m sure that the tire store or the shop did not drive your car that fast. It is a very intimidating car.
I suspect a bent wheel since thousands of otherwise earnest and qualified techs have balanced a bent wheel to Zero imbalance only to have the car still shake on the road. Slightly less likely, but still possible, is a bad tire. It is possible to have a totally new tire with a “slipped belt” make it past the quality-control robots and make its way onto your car, which will also cause a shake no matter how well the tire/wheel combo is balanced. Unless you have hit something hard enough to bend a wheel, AND the suspension, a harmonic shake won’t originate with the chassis. MC
Q – I have a ’64 Porsche 356C Coupe — 6-volt — that has an electrical system that’s not 100% happy. Apparently the charging system is not quite up to the task as a month or so ago I drove to Columbus for an event and half way through the weekend had the battery down enough that it wouldn’t restart the car.
Fortunately, two 6v Optima batteries fit where the original lead-acid goes so I carry a spare. It happened again last Saturday at Woodward — stopped for gas and no restart. I’m not an electrical wizard and am looking for help. Up for the task without costing me a fortune? – Chuck
A – That spare Optima is a great idea! Every August I get the same calls, “I stopped at the store, came out and the car won’t crank” And when the car is left to cool off, like a miracle, it starts right up!
I feel fairly well versed in these problems and I suggest solving it scientifically…by testing. The 5 volt charging system is a serious problem that enthusiasts face with the lack of reliable parts. The current challenge is a lack of 6 volt regulators. Even NLA who is an acknowledged leader in 356 goodies has been flummoxed. Many who want to drive their cars regularly opt for a 12 volt conversion. Parts are much more readily available.
Rather than burn more ink in this column, go on-line and access all the P4 articles on this and many topics at the SEM/PCA website. Good luck and remember, a fortune is a relative thing. Ask anyone with big 3 stock.
Q – I just changed the oil on my 944 turbo and when I started it up, I got no oil pressure. As I checked it out, I noticed the power steering pulley wobbling. I then checked the crank bolt and it was loose so I tightened it. I still had no oil pressure so I shut it off right away and took it apart I removed the front of the crankshaft and inspected the oil pump and every thing looks fine! I have been sitting on this problem for a year and I am at my wits end. – Stan
A – Okay, there’s really two questions in one here, and I’m going to answer the last one first. The power steering pulley is probably bent by being tightened down cockeyed. It sits in a relief at the end of the crank and it is easy to simply tighten it without holding it centered. That is probably why you found the crankshaft bolt loose after you tightened it. I know that whenever I tighten something that then comes loose, I wonder if it is early stage Alzheimer’s or what! Naturally the pulley sits very deep in the crankshaft main pulley so you can’t even see where you are working.
Oil pressure loss is freaky but It has happened to me too. Fortunately never while I was driving the car! Following a number of operations on the 944, the oil pump prime can be lost. I solve it by pressurizing the crankcase during cranking with the spark plugs removed. Pressurizing the crankshaft pushes the oil from the pan to the pump and removing the plugs lets the crankshaft turn faster. This builds pressure without any significant load on the engine bearings since you never want the bearings to run dry of oil. This combination does it every time. – MC
Q – After washing my 08 Cayman and letting it sit overnight, next morning, the brakes seem to be seized. I can break them loose by tapping the accelerator pedal but applying the brake pedal doesn’t help. Is this normal? Do the pads oxidize and bond to the rotors? My car has the manual shifter. This happens only when the car sits after washing. – Mark H.
A – You are correct, the pads are corroding to the rotors overnight. After washing the car, I suggest that you drive the Cayman at a speed of about 50 to 70 miles per hour then apply the brakes to evaporate the water. Problem solved. MC
Q – I had a problem with my night vision so I picked up a pair of higher output bulbs and installed them in my 89 Carrera. Last night and I smelled an odd odor of burning rubber and no, it wasn’t my tires. It caused me some concern but then on the way home, the odor went away. I did notice that everyone was flashing their lights at me and when I tried to dim the lights, the switch felt like it was working but the lights are on bright all the time. – Paul
A – On these early cars the power for high and low beams flows through the dimmer switch rather than through a relay. (Remember that the car was designed in the sixties.) And if that isn’t enough, when you put bigger bulbs in the headlights, the switch melts even faster. It is not easy or cheap to fix the switch and it involves getting under that dash in ways that aren’t kind to those wearing bifocals or who have vertigo.
To avoid this problem in the future, have relays retrofitted under the hood. Essentially the load that originally passed through the switch will now pass through the relay. I guarantee that you will never fry a switch again no matter how strong your bulbs are. The added benefit of relays is that the headlights will be brighter since power is relayed directly from the battery to the lights. – MC
Q – I just had new tires installed on my 86 Carrera and when I took the car to the tire store, after they balanced the tires, they left the old adhesive on the wheel. What do you use to get that off? David
A – Try “Goo Gone” to remove the old adhesive. It may take some elbow grease but be patient and do not use an abrasive to save time. As an aside to that adhesive problem, if you have clods of tar on the wheels, you can use an ice cube to chill them and then they pop right off the finish when you nudge them with a Popsicle stick or a Teflon spatula. Don’t use anything hard or sharp. – MC
My 944 Turbo has a problem with clutch disengagement. About three thousand miles ago, I had a high performance clutch and flywheel set up installed and it was working fine. Gradually I noticed it harder and harder to shift and finally I could only start the car in gear if I wanted to drive it. And it grinds when I try to engage reverse. Prior to the total failure of it, I was having a tough time getting the car into second gear on both the up shift and the down shift. Even when it was working fine, second gear did not feel healthy. I tried to adjust the clutch master cylinder free play and when I look at the clutch fork through the inspection hole, it appears to be moving as far as it should. My fear is that I have damaged the transmission and that I will have to have the clutch replaced again. I provided the clutch parts and the work was done three years ago so I know this is going to hurt. Jerry
A – I am sorry to tell you this but you are correct. Turbo clutches are a bugger to install with all the extra parts involved not to mention your 4 inch exhaust. Even worse, the high performance clutch supplier won’t warranty the parts based on the time they have been installed in the car. To add insult to injury, the odds are pretty good that your transmission synchronizer in second gear is toast.
The most recent failure that I have seen involved a failure of the clutch release fork. A heavy duty clutch puts greater load on an area of the fork where it seems that the casting was just a little too thin. When I compared the damaged fork to another newer part the broken area was reinforced. These parts are now considered obsolete by Porsche so your only option is finding a good used one. The other possibility is that one or more of the pressure plate fingers has broken or warped. The only way to know is to get it all apart and call it as you see it. Just getting at it is the truly painful part.
As far as the transmission grind into second, the rated time to rebuild a 944 Turbo trans is about 15 hours plus the parts involved so if the clutch issue wasn’t enough, it is only wise to have the transmission serviced at the same time to take advantage of the fact that it has to be removed to do the clutch a second time. Once you get it sorted out, I would love to test drive it. I bet it is a beast. MC
Q – Some of the questions in this column seem unbelievable. Do you make this stuff up? Chuck
A – Someone said: “truth is stranger than fiction” and I don’t have to make it up, it just comes to me from someone’s curiosity, their experiences at mine or another shop, and then there are the club parties and events. The best questions I get come from club members who button hole me at an event and just want to talk. Sometimes I feel like a grief counselor, occasionally an educator, but I am always interested in your feedback. If you have a question, I will be happy to answer it in a non partial constructive way. Just let me know if you don’t want it discussed in this column! My number is 248-245-5424. You can call anytime and leave a message if I don’t pick up. MC
Q – The check engine light came on in my 2001 Boxster and I wonder why. The car still seems to run well and with no symptom present, I think it is OK to drive but that light bugs me. When I called the shop, they said as long as it is not flashing, I could drive it in.
A – When the “Check Engine” light is on but not flashing you are usually correct. With no symptom I would not worry about it. I would call it more of a justifiable concern. When you take it in, you should expect your advisor to test drive the car and note their observations and recommend a “computer scan” and reset.
The technician will access the vehicles OBD II interface, extract & save the stored codes and print out a report. If your advisor is knowledgeable about the topic they will then recommend a proper course of diagnosis appropriate for the fault codes. When there is no symptom present, the best course of action might be to clear the codes and attempt a reset, sort of like closing a program on your computer and restarting it.
Following a reset, then your adviser should test drive to confirm that the symptom is gone and that the codes do not immediately reassert themselves. When codes come back right away, I call that a “hard fault” and I would suggest that those be investigated using technical service bulletins and a diagnostic trouble tree provided by the manufacturer. Hard faults are sometimes easier to track down.
The tricky ones are the “soft faults” or intermittent faults where the code may not come back for a number of miles, days, weeks, or longer. Occasionally I will drive a car with the computer attached and take live readings from various sensors during a road test to try and catch the car “in the act”. I do not actually take the readings, I have an assistant do it. Multi-tasking while driving is not an acceptable diagnostic process!! The tricky soft faults sometimes involve 10 to hundreds of miles. To have a client with the understanding of this process and a desire to get to the bottom of the problem is most appreciated.
The important thing to remember is that the code extraction and reset operation is intended to access the vehicles fault memory, retrieve and analyze stored codes and it is just the first step in a diagnostic process. Unless there is a “phantom” code, it will not correct most issues.
So the good news is that your car is still running well and the bad news is that in most cases, the check engine light will come on again. If and when it does, I would then recommend spending some diagnostic time to determine why. I usually do not suggest spending any more time on a check engine light unless the fault is repeatable, if further problems can occur if ignored, and if you have the budget for it.
If you ever notice that warning light flashing that is another story. A flashing check engine light indicates a problem that could potentially damage the car, and
In that case, pull over and strongly consider other options for getting the car in to the shop. If that flashing light is accompanied by reduced performance, odd thrashing noises or smoke, you already know the answer to this one. MC