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JFP in PA

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Everything posted by JFP in PA

  1. Welcome to RennTech The DME MUST be the correct one for the car, and the car’s keys, immobilizer, and DME must all be coded to work together. That will require access to the PIWIS system to complete, after which you will need to address all of the car’s system control modules to get everything successfully talking to each other.
  2. Doesn't happen because the car the family is in had a 700-800CCA or so battery with loads of current reserve. But with a lightweight battery with limited current reserves (read amperage), it would definitely be a possibility given enough time.
  3. I would not bet on that, modern load testing equipment can load test the alternator in the car, and can even test the diodes' with it in there. Units can be pricey, often $4K (US) or more, but will test the entire system.
  4. Sorry, but no, voltage and amperage out put of the alternators in question were dead on rated spec for the vehicle involved, and remained so under load; the weak spot was the amperage reserve, not the voltage reserve, in the battery during periods of high demand. 😉
  5. No one here is "demeaning" your postings. Our intent is to help people with problems, and provide some educational context for all readers to consider when considering potential purchase decisions. My comment on headlights dimming was a real world experience that has occurred more than once when customers with light weight Li batteries brought cars into the shop complaining of these problems. Subsequent testing showed their charging systems were performing completely within normal specs, but when the AC clicked on, or a strong base section hit the stereo system, the lights dimmed
  6. The Li battery business is suffering from a similar problem that the light bulb business had when switch from incandescent to LED. People had long associated bulb wattage with light level output, even thought wattage was actually measure of how much energy the bulb consumed and heat it generates rather than light output levels. So when consumers saw that an LED replacement for a 7 watt night light bulb only used 1.3 watts of power, their immediate assumption was that the LED would be much dimmer in light output than the incandescent bulb, which was anything but correct; and that stalled acce
  7. He also went on to state that you could use their lightweight Li battery in a daily driver, "..as long as it is not used in cold weather.", without defining how cold that weather really was. Li technology for automotive use is a relatively new and evolving technology, and a very interesting one at that. But like most emerging tech, it still has a bit of the "wild west" in it that will shake out over time, but using "equivalencies" that seem purposely deceptive to sell the products is not helping their case any.
  8. Here is an interesting published statement by a representative of the Antigravity Li battery company about their use of "equivalency ratings" used by Li battery manufacturers: "Unfortunately for you consumers....the waters are muddy because none of the lithium battery company put the ACTUAL and REAL Amp Hour of the Capacity ON the Battery itself.... For example most of the battery companies including Antigravity go by a "PB-EQ" (means-"lead-acid equivalent") rating which is essentially stating what size our Lithium Battery is roughly equivalent to the Starting ability of a Lead/Aci
  9. If there is one thing all Li batteries do not like, it is being overly discharged (read deep cycled), which really damages them. This is why many newer Li batteries have a "BMS" or electronic battery management system included in their construction, which will step in and cut off the battery before it gets into an overly high discharge condition. Most Li battery BMS systems also include thermal protection as Li cells do not like getting very hot either.
  10. Li technology is very interesting, but also quickly evolving. One way to look at light weight LI batteries to to watch what happens with race teams at the track; most serious race cars run Li lightweight batteries with one major caveat: they don't use them to start the car, only to supply energy reserve while the car is running. For starting in the pits they hook up a conventional AGM battery: There are Li batteries that are fine for daily drivers, with high CCA ratings, but they are also not super lightweight and expensive because they are relatively low production i
  11. But otherwise the underlying battery appears to be the same unit.
  12. They both appear from their dimensions and other specs to be the same battery ("Starter Battery - 68Ah EqPb lead-acid/AGM/GEL equivalent", etc.), but with different terminals.
  13. If it truly was, it would be purely luck. Interestingly the battery manufacturer's website says, and I quote, "up to 400CCA for ICE engines in HYBRID models with 900CA available at the press of the button" (notice we are jumping from CCA @ 0 F to CA ratings @ 68 F in that statement), apparently referring to its reserve cell capacity when a button is manually depressed, but at 68 F, not 0 F; and goes on to state, "Specifications: 68Ah PbEq, 400CCA with Push Button Reserve", so at 400 CCA (without the manual reserve button depressed) it has about 1/2 the cold cranking power of a conventional or
  14. Actually, it is not. You simply cannot take values for a smaller battery and extrapolate them to a larger unit, or visa versa. There are many other factors (internal conductivity, heat retention, cell pack, conductor resistance differences, etc.) that complicates such a mathematical solution attempt to the point of being unreliable. This is why battery manufacturers continually test their batteries to see how they rate rather than attempt calculated performance projections. If it was simply a matter of extrapolation, life would be a lot simpler in the battery business, they could save a who
  15. As someone that spent a significant part of his career in the battery business, your use of "assuming the proportions are the same" is more than seriously flawed. The CCA test used by the BCI (Battery Council International, the international technical consortium that sets standards for battery ratings and testing procedures used by battery manufacturers world wide) is very similar to the one used by the SAE (Society of Automotive Engineers); which requires storing the finished and fully charged battery a 0F (-17.8 C) for a period of 24 hours, then load testing it to determine its CCA rating.
  16. I would also like to know the unit's cold cranking amperage (CCA run at 0F after 24 hours), not the cranking amperage (CA which is done a 68 F) in the specs. A lot of these small, lightweight units are fine for race cars, but fall flat on their faces (literally) trying to spin over an engine at 20 F.
  17. We always did it on a lift with an engine support bar under it before we undid the mounts. You only need to drop it a couple of inches to make getting at it much easier, not out of the car. Usually, the nut on the ground is not in bad shape, and a quick spray with a good penetrating oil always helps. Just be sure to wipe it off before putting it back together again, and put a small dab of anti seize inside the nut.
  18. Depends upon how large your hands are, dropping the engine down slightly always gives you more room.
  19. The correct test for the primary cables is voltage drop rather than resistance. No primary cable should show a drop of 0.5 V, if they do, they should be replaced regardless of what resistance testing shows.
  20. No, but hard clutch pedals in these cars is usually a sign the clutch itself is on its way out,
  21. Good luck, these types of issues are diagnostic time consuming; with luck you have a wiring or connector issue.
  22. Your next step would be to see if the DME is actually seeing any signal from the CPS, which requires a PST II, PIWIS, or similar oscilloscope diagnostic tool. You could also check the wiring harness for continuity to the DME; pin 1 on the sensor should lead to terminal 78 on the DME, pin 2 to terminal 20, and pin 3 to terminal 28. If any of those circuits shows a lack of continuity, you have a wiring issue.
  23. Unidentified sounds like this can be something small, like a loose part, or they could be something much more serious. Unless you can isolate the sound source, I would recommend not driving the car and flat bedding it to someone that can do more intensive diagnostics for you.
  24. I think the biggest obstacle you face is the leveling system, as even though you fit the mechanical parts, your DME does not have the programming to make it work, and even Porsche has proven to be reluctant to reflash the computer for this purpose. And without that, the car will fail inspection anywhere in the EU. The washer stalk does have a distinct cap which indicates the action required to activate the washers. This is a file done by someone that tried this, but it does not address how to get the DME functional: http://986forum.com/forums/attachments/perform
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