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  • Porsche Club
    PCA (Porsche Club of America)
  • Present cars
    1999 Porsche Boxster
    1985 Lotus Esprit

MNBoxster's Achievements


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  1. Hi, That fluid is absolutely not recommended for the Tiptronic S! I contacted ZF-Getrieb directly with this question and their reply was that only ESSO ATF LT 71141 was the proper Fluid to use. Also, that use of other Fluids can accelerate wear to the Clutches. Hope this helps... Happy Motoring!... Jim'99
  2. Hi, I think your Evidence is purely anecdotal and your Cause and Effect totally circumstantial. There is waay too much mysticism surrounding this totally innocuous length of tubing. The snorkel is a Noise Abatement Device to comply with Noise Abatement Laws prevelant through Europe. Porsche leaves it on ROW models to prevent the cost of redesigning the intake. I de-snorkled my Boxster 3 mos. ago and haven't seen even a 0.1% drop in my MPG. In fact, we took a Sunday Drive through the Wisc. Backroads last weekend to see the Color and I got 30.1MPG on the Expressway getting there (on Cruise Control - 65MPH) and 26.9MPG through the twisties (although we weren't pushing it, we were averaging 55+ MPH). I've read it was to prevent water from entering the engine in the rain and this is a bunch of Bull! You'd have to drive through Katrina before this device would serve this purpose. The Boxster Engine draws in so much air, that any water getting in the Intake and travelling to the Plenum is so diluted as to be more akin to very moist air. The Filter will trap most of it and the quantity of Air moving through it will pick-up the water mostly as a mist. So far as directing the Air to the Engine, again Aaaaannnnnhhhh! The Engine will draw all the Air it needs and the capacity of the Intake and the Filter exceeds the demand of the Engine. I also own a Lotus Esprit which has it's sole intake in roughly the same position as the Boxsters (although a few inches higher). I have driven it through torrential rains and never had a problem, nor have any other Esprit Owners I know (and I know most of them - Nationwide). And this car, because of the Turbo draws at least 4 times the Air a Boxster does. I'm not so much trying to disprove your theory as alerting you that the problem you experienced lies elsewhere. It may have been a BrainFart by the ECU (DME in Porsche Parlance), a faulty MAS, a stuck Vac valve or the like, but it certainly wasn't the lack of a snorkel. Happy Motoring!...Jim'99
  3. HI, Take some double-sided Foam tape and cut it down into thin strips then attach it to the Roll Bar and insert the Windstop. The Tape will do two things; it will adhere to the Roll Bar and Windstop and it will act as a wedge to make the windstop tight. It works great. Hope this helps... Happy Motoring!...Jim'99
  4. Hi, Once a Tire has been punctured, even though it can be repaired (if a Tread Puncture only), the Tire has been compromised and should NEVER be driven at excessive speeds. Once a Tire is repaired, it's ability to shed heat is also impaired, especially in the area of the repair. Driving at excessive speeds can heat up that part of the Tire to where it can delaminate or a Blowout can occur and is simply Foolhardy and irresponsible. You don't want either of these things happening at high speed. There is only 1 proper method of repairing a Tire. The Tire must be plugged, but also patched on the inside[/u] over the plug. A plug alone should never be used and any shop performing such service should be avoided. The Tire must be demounted and visually inspected on the inside to insure that there is no damage to the cords, if so, replace the Tire. See the NHTSA's recommendation on Tire repair here: http://www.nhtsa.dot.gov/cars/testing/ncap...MaintRepair.htm Now, considering that you are going to have the tire demounted, repaired (if possible), remounted and balanced, this will run a few bucks and you still end up with a compromised Tire. If your Tires are more than halfway to the treadwear bars, it may be best to hink about replacing the Tires, at least on the affected axle, especially if you are going to drive at high speeds. Even if you are willing to take the risk, consider that you are also asking everyone else to unwittingly take the risk with you. Personally, I don't think it's a risk worth taking... Happy Motoring!...Jim'99
  5. Hi, If you had any sort of air leak, you'd be exhibiting a Lean condition if the leak occurred downstream of the MAF (since it would have allocated Fuel for a lesser mass of air going to the intake). If it occurred upstream (and the MAF was functioning properly), it would account for the additional Air Mass and allocate more Fuel. If you had a clogged or partially clogged Fuel Filter, again less Fuel (or a Lean condition) is more likely. This makes a faulty MAF and/or Faulty O² sensors the most likely culprits. Since it's unlikely that the O² sensors from different Banks would fail simultaneously, this makes a faulty MAF sensor the most likely possibility. Hope this helps... Happy Motoring!...Jim'99
  6. Hi, One caveat, if you push the wheels too far out, you run the risk of scarrring the side panel with all the gravel and peastone you'll toss at it. Happy Motoring!...Jim'99
  7. Hi, I knew one of them was backwards, I took a shot and said the engine. Now that I think of it, it should be more likely to be the tranny. Thanks!... Happy Motoring!...Jim'99
  8. Hi, Uh... not to state the obvious, but on the 996, the tranny is on the other end. This means that the engine turns the opposite direction. So it's also necessary to transplant the tranny. If not, you'll get 1 Forward Gear and 5 Reverse gears...;) Happy Motoring!...Jim'99
  9. @jnc, To clarify, you stated that "AFAIK... Diodes, should have no ripple. They take AC and turn it into DC. I would think if they have a ripple, then they are bad." This isn't exactly correct. True a Diode should not have a ripple. But, as in my description of how the Alternator works explains, essentially, you have three (3) separate pulses (for lack of a better term) of current being produced. There is a slight delay between these pulses and this is the ripple which is being detected. So, there should be a ripple detected, if not, then one or more of the 6 Diodes (because they exist in pairs), not the 3 which you mentioned would be Bad. Also, you mention that "Generally speaking, if the Alternator light is on, that means the battery voltage exceeds the alternator voltage... " Again, not exactly. You need to understand that unlike a Car with a Generator, in a Car equipped with an Alternator, all of the Car's electrical needs are satisfied only by the Battery. The Alternator only supplies power to the Battery, no other Accessories. This is necessary to smooth out the effect of the current pulses or ripples which the Alternator produces (The Battery can be charged in Pulses. But, other Accessories, such as the Stereo would not operate very well with a pulsed current flow.). Also, the Warning Indicator is not the Alternator Light, it is a Battery Warning Indicator and means that the Battery is Low or won't accept a charge. There are many reasons for this including a Short Circuit to the Battery, Cracked Cells in the Battery, Low Electrolyte level in the Battery, loose or missing Accessory Belt, and possibly a failed Alternator. In other words, the fault isn't automatically with the Alternator. Finally, you state "If the light glows dim, that means some AC is leaking in the electrical system..." Again, nope. AC and DC are incompatible. AC cannot leak into the system. If a Diode fails, the current flow through that Diode either cancels out, or stops flowing. Hope this helps... Happy Motoring!...Jim'99
  10. Hi, There are a lot of smart guys on this forum (much smarter than me), so I thought someone would have jumped in to explain what was really happening and how to simply test your Alternator. Since no one has, I thought I'd give it a go. To begin, an Alternator is not a very efficient way to produce electricity for a car. First, it produces Alternating Current (AC), which the car cannot use, so Alternators must rely on diodes to rectify their AC output and convert it to Direct Current (DC) which the Car can use. Second, an Alternator requires two watts of energy to spin it for every one watt that it produces. It's advantages are that it can produce large amounts of current relative to it's size, and it can produce large amounts of current at idle, things a generator does not do very well. The Lundell Alternator, technically the proper name for your Alternator, is really three Alternators in one body. Each of the three sections of the alternator generates Alternating Current (AC). In one revolution of the alternator it puts out three separate currents. These currents are each out of phase with the other two sections. Since the complete cycle (one revolution) of the Alternator is 360 degrees, each of the three phases are shifted by 120 degrees from the next phase. Each of the three phases has its own windings in the Alternator and each of the windings has its own pair of Diodes. Because the Alternator generates AC current, each of the Diodes in a pair have their own polarity - one positive (+) and one negative (-). The negative bridge of the Diode connects directly to the Alternator housing, which is of course grounded to the Engine Block, while the positive bridge connects to the output stud, which then goes back, via a cable, to the positive (+) terminal of the Battery. The Diodes function is to block the current from one polarity while passing through the current from the opposite polarity (this is why you have two of them for each phase - they each function in opposite ways to each other). This is how they convert the Alternating Current (AC) to Direct Current (DC). The Diodes (or Rectifiers, because they Rectify the current), are usually arranged in pairs with all six being located on a single IC board or chip. Because of this, you get some rippling DC in the Alternator's output if everything is operating properly (this was the test the Auto Store conducted). But, the Battery smooths this out to regular or smooth DC. These Diodes last only so many thermal cycles. Some of the newer Avalanche Diodes are even designed to be self-sacrificial by shunting large output spikes to Ground in order to save the sophisticated on-board electronics found on today's cars. Modern Alternators also produce high output from a very small package, which means that the case is not a large enough to act as a Heat Sink. The high heat which consequently builds up helps shorten the life of the Diode chips significantly. Now, since each of the three phases has its own windings in the Alternator and each of the windings has its own pair of Diodes. Each of these windings and/or Diodes can fail, one set at a time. If this happens the Alternator can still run the Car, it's Accessories and charge the Battery, but only with a limited current, approximately 2/3 of its original capacity if one system fails. If two systems fail, then it puts out only 1/3 of its rated capacity. What this means is that a failing Alternator can go unnoticed for a long time, because unless you are using the bulk of the Car's Accessories at one time, the limited output of the failing Alternator may still be sufficient to meet the Car's needs. The Alternator will continue to fail until finally, there is insufficient output to run the Car, it's Accessories and charge the Battery. The first you may notice is the Headlights are dim, or the Dash Indicator lights, or the Stereo starts to whine, or worse, the Car fails to start (as Luck usually has it, typically late at night and in the rain). Before suspecting a failed Alternator, you need to eliminate other possible causes. Check the Accessory Belt to insure that it is tensioned properly, usually no more than .5" movement when you push it with your finger (car OFF of course). Next, with the car OFF, check the voltage across the Battery terminal with a Voltimeter/Multimeter (set to DC scale), it should read at least 12 volts, more is better. If all these things check out properly, then the Alternator becomes suspect. To begin, start the car, make sure all the Accessories are off and increase the RPMs to a fast idle. Set the Voltmeter/Multimeter to the DC scale (not AC or Ohms). Measure the voltage across the Battery terminals - red (+) lead of the Voltmeter/Multimeter on the positive (+)terminal, black (-) on the negative (-) terminal. The voltage should, read between 13.0 - 14.2 volts. If it reads less than 12 volts you most probably have a failed Alternator. If the voltage reads OK, (with Car still running) turn on the the Stereo, the Headlights, the Rear Window Defroster, the Heater, and anything else that draws power. Increase the RPMs and watch the Voltmeter/Multimeter. It should still be reading around 14 - 14.2 volts. If it reads lower than 13 volts the chances are that your Alternator is not operating properly (or fully, as described above). Finally, you want to check the Field Voltage. In order for the Alternator to generate electricity (because it lacks the permanent magnets of a Generator) it must first be supplied with a Field Voltage. If you know which wire is the one that supplies the Field (normally labeled 'F') then simply check with a Voltmeter/Multimeter to see if there is at least 12 volts at the Field. Another way to check this is to use a paper clip, small screwdriver, or anything Ferrous (iron, Steel). Hold it near the side of the Alternator with the ignition switch turned in the ON position, engine OFF because you don't want to have your hand near the spinning pulley/belt. If there is a Field Voltage present then the metal will be attracted magnetically to the side of the Alternator, not very strongly, but you will feel the magnetic attraction. One last thing to check is the Bearing. The rotor inside the Alternator rotates on Bearings, and these can fail. When they do you will hear a loud grinding noise associated with the Alternator. To isolate the noise take a length of tubing, Heater Hose will do fine, put one end to your ear and move the other around in the vicinity of the Alternator. The noise will be much louder when you point it at the Alternator if that is the culprit. To further confirm this, you may disconnect the Accessory Belt and spin the Alternator by hand. If you hear, or feel a rumble or grinding then the Bearings have failed. Even If you don't hear a noise it may still be the Alternator Bearings since the Bearing might be smooth without the tension of the Accessory Belt. Also, check for side play in the Pulley. NOTE: NEVER operate the car without having the Battery connected. Without the Battery, or if either the positive or negative cables are not hooked up, voltage can rise to over 40 volts!. This will cause extreme damage to the Car's very expensive electronics. FYI, in an effort to increase their reliability, Alternators are becoming water-cooled. A 5/8" take-off connects to the Car's cooling system. Keeping them cooler will extend the life of the heat-sensitive Diodes. The 4.6L Cadillac NorthStar Engine currently uses a water-cooled Alternator. This is going to become more prevelant as Manufacturer's move to 36 Volt and 42 Volt electrical systems, because of the greater efficiency they provide (this is exactly why 12 Volt systems were adopted over 6 Volt systems). This switchover will occur before the 2010 model year. Hope this helps... Happy Motoring!...Jim'99
  11. Hi, I know I read somewhere about Porsche adding 6-8 HP to the TipS cars over the Manual to compensate for Parasitic Loss due to the Torque Converter. I was especially struck by both how innovative and forward-thinking this was, and that no other car that I know of does this. Because of the small increase, I assumed it was accomplished by the DME. It may take me a couple days to re-locate the source, but as soon as I do, I will post it here. Happy Motoring!...Jim'99
  12. Hi, For NA cars, going Cat-Free will have minimal gains, if any. The reason is that some Backpressure is desirable to maximize the scavenge effect of the exhaust. Reducing the scavenge effect (because the exhaust pulses are elongated) will rob some HP and these effects are most seen on the Low-End. Add to that, the Cats today are much more Free-Flowing than even a few years ago, meaning that removing them simply doesn't yield that much of a Net gain. Then, as you mention, the ECU (DME in Porsche parlence) will go into a default MAP if it sees things which are too screwy, resulting in a lessened performance, especially in the Mid to Upper power band. On a Forced Car, on the other hand, especially a Turbo, going Cat-Free can have significant gains. The Turbo usually provides sufficient restriction on it's own and the increase in EGP (Exhaust Gas Pressure) can be used to either make more Boost, and/or reduce Lag, both performance enhancing things. Happy Motoring!...Jim'99
  13. Hi, I did a similar Hack, but put the opener in the Center Concole, kept the 9 volt and used Velcro patches too. I used a MO switch and a small LED Indicator light (easy wiring scheme) installed into the Blanking Plug for the Heated Seat Switch (don't have 'em). This way, the switch is within easy reach and I have an indicator light showing the opener is working. It came out looking very good, looks stock, no one notices it (and that's the point). Happy Motoring!... Jim'99
  14. Hi, Sound will deepen, performance gains are moderate to non-existent with a potential drop in low-end performance. You will have operating issues if the 0² sensors aren't dealt with. The DME compares the voltage readings of the pair of 0² sensors dedicated to each bank both pre and post-Cat and between each pair (OBDII). I know that for the Boxster, the distance between the two is also significant and there s/b a voltage difference as well. If the DME does not read this, it will run/start poorly. I know that for the Lotus Esprits (I own one too), the fix is to add a certain value resistor on the 0² wire(s) which tricks the ECU into sensing a proper set-up. I don't know if this is the fix for the Boxster. Happy Motoring!...Jim'99
  15. Hi, My understanding is that there is a difference between the engines for a TipS and a Manual. Porsche slightly upped the HP for the TipS engines to accomodate Parasitic Loss from the Torque Converter. Of course, this may merely be a function of the DME Maps, that I don't know. Happy Motoring!... Jim'99
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