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laalves

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Everything posted by laalves

  1. For quite some time the feel of my brake pedal (02 TT) doesn't feel right, spongy and easy to reach the bottom. Stopping power feels ok, but need to go deep on it. Brakes were just bled at the dealer, no change in the feel. I didn't discuss any of this with them, as I'm used to do all my corrective maintenance and only let them do the minimal scheduled so as to have the stamps on the book. Having another person pressing the pedal whilst I look at the Master Cylinder/booster/ABS pump area, engine off, there's lots of unexpected noises: clear spring noises coming from inside the MC and bubbly/squishy noises that appear to come from the lines going into the main ABS controller unit. No leaks are visible anywhere. No bubbles are visible on any of the unions. Another thing that has puzzled me for a while, is the appearance of drops of hydraulic fluid on the surface of the fluid reservoir. Some ends up collecting in the channel surrounding the reservoir. It's as if it is leaking through the cap, although I have replaced it with a brand new OEM cap. The level of the reservoir does not go down with time, never had to top it with fluid. Anybody had any of these symptoms? I'm tempted to either replace the MC (750€, not a trivial cost) or to take it out, open it and check the seals. Not sure about this option either because I may end up buggering a good and expensive thing and not solving the problem.
  2. I also had both for years. I did an overhaul of my SAI system during the COVID lockdown, replacing both of the 20-year old diverter valves with 710P from a VAG dealership (one of them did not hold any pressure), replaced all Pierburg electrovalves, Ts, Ys, Xs unions and some of the piping. Result: P0491 disappeared, P0492 still there. I can hear the pump working at startup, testing it with Durametric works fine, so that shouldn't be it. Still scratching my head, but truth be told, I haven't done a leak check yet (which I should have done first) but already got the plugs to do it, just need to find the time.
  3. Sorry, nope, at the bottom of my list of priorities at the moment...
  4. If you are even considering that, that's because you don't really like the car and should sell it. To me. For cheap.
  5. Here's official information for the US: https://www.nhtsa.gov/equipment-deta...643749#recalls Quite a few interesting technical details.
  6. Here's official information for the US: https://www.nhtsa.gov/equipment-deta...643749#recalls Quite a few interesting technical details.
  7. Just read this: Safety problem with Ohlins R&T on 996 turbos - Rennlist - Porsche Discussion Forums RENNLIST.COM 996 Turbo Forum - Safety problem with Ohlins R&T on 996 turbos - Just saw this on Facebook, sent an email to Ohlins EU and they... I bought mine on 06/2018 from design911.com and installed them on 09/2018. No problems since and very happy with their performance but now I’m concerned. Design911 confirmed this to me today but they have no further details. Also wrote to Ohlins directly but had no replies yet. Will post this in the Carrera forums as well because of the 4S guys.
  8. Sorry, but i have to insist. Cars are not designed that way, they do not draw from the battery at idle, batteries would not last through a single winter of urban traffic jams as they would never be recharged after they started the engine. There's no point in continuing this discussion.
  9. Family in new car, dead winter, night, snow storm. Car goes off-road and gets stuck in snow in the middle of nowhere. Car is idling, heater at max, radio playing, headlights on, window defrosters on. Alternator not putting out enough current and needs to draw current from the battery to keep everything running, "as designed". After a couple of hours, battery dies and the engine follows suit. Family dies. Manufacturer says: "Tough luck, car was working as designed". Doesn't happen in a car working to spec.
  10. Sorry, that cannot happen in a modern, well functioning car. If it were, cars would not idle for long. Battery would be depleted and there would not be enough current to keep the car running. If they had big aftermarket amplifiers then that surely can happen. Stock consumers, that doesn't happen. That's why the bassbombing crews install bigger alternators, bigger batteries and capacitors to increase available current reserve to feed the monster subs. To have all that working properly, it may even require an ECU remap to compensate for increased idle torque due to the bigger alternators. That's what they do in police cars. As the loads increase, the regulator compensates the voltage drop by letting more current flow through the exciter which in turn increases the magnetic force generated by the field, hence causes more drag on the engine and the ECU injects more fuel to compensate for the added necessary torque. Engine RPM changes little, output torque increases what is required to put out more current. There is no way to properly test an alternator in the car, only in a bench, there's no way to cycle it to max load and back in the car.
  11. Any recent car has an electrical system designed to not let that happen, if working per spec. The alternator produces enough energy to all the consumers in the car at all regimes. The 996TT has a nominal 150A alternator which provides max current, if needed, already at idle. AFAIR, those Bosch alts max at 1300rpm (alt rpm, not engine). It's just 2.8HP stolen from the engine anyway. If a consumer requests more current, the regulator ensures that it is provided. What that behaviour tells is that the alternator and/or regulator were not to spec. From the moment you turn the engine on, the battery is not doing anything other than getting recharged from the starting effort. As one throttles up and down, the battery will serve as a sink that will smooth out voltage peaks, shielding the electronics from those peaks. Other than that, start the engine and take the battery out if you want to, engine will continue to turn happily, lights will remain on, music will continue to sound. Possibly fry the ECU as well since voltage peaks will not be filtered. If those cars needed a battery to have basic, stock consumers working properly at idle, the alternator and/or regulator was shot (or there is a severe current transmission issue) and those new batteries became very old very quickly because they wouldn't get properly charged.
  12. Let me try to get this thread back to its original intent: I bought a new interesting toy for my car and am sharing my experience with the other members. I have learned a lot in this forum, much more than I have given back and occasionally I try to share a bit of my knowledge and experiences here and in other forums I participate in. For quite a few years, I have been also giving back in financial support to help keeping the place up and running. Let me also make a disclaimer: I don't work for or in any way am affiliated or have any interest in battery manufacturers, resellers, car dealers, workshops, race teams, whatever. I won't also go on to claim high levels of technical knowledge or authority on anything and certainly this is not the place to do so. You can look me up in Linkedin, that's where I believe to be the place to ruffle professional peacock feathers to try and get attention to gain some professional and hopefully, financial advantage. If you find me there, you can have an idea of my level of professional technical knowledge, if any. I come to places like this to have fun, proudly showing my toys and enjoying somebody else's as well as looking for help in solving technical problems and giving back when I can. I don't understand why this is happening in this thread, an insistence on demeaning a toy, copy/pasting specifications of a different battery to try and make a point against another battery because they look the same? What is this? Further, claiming that lithium batteries are no good to start a street car because one race team in one competition starts their cars with off-board AGM batteries and then switch to on-board lithium, thereby lithium are no good for street cars, is laughable. What do racing conditions and hardware have to do with street cars? Guess what, many race teams in many competitions change Michelin tires twice per race, thereby Michelin tires are no good. In these few days of use, this battery has been performing beautifully in the car, starting it without hesitation or hiccup and showing no signs of lack of power under any circumstance. If you have seen cars with their engines running and having issues with headlights dimming when the stereo or AC was running, then I suggest to check the electrical system in other elements other than the battery since that would be unrelated. Let me very clear, again: I'm not claiming any kind of superiority of the battery I bought over any other kind. I don't care. I'll be reporting back on this thread on my experience over time, so that others may have an idea on how good or bad this particular battery is for this particular application: Porsche 996 Turbo living in a temperate climate and sleeping every night in a garage where temperature never goes under 18ºC.
  13. This is my battery: This is the one you were talking about: In the box you get screw-on optional SAE terminals. It appears that in Australia they supply brass and the European distributor supplies aluminium ones, which are the ones you can in my car. They can be screwed on in multiple ways, as convenient. In my case, I screwed them on sideways, otherwise the battery cables would not reach the terminals.
  14. Now I noticed where you picked that, it’s the wrong battery: Lithiumax RESTART9 EV/HYBRID Series ULTRA-LITE Vehicle Battery | Lithiumax 2020 WWW.LITHIUMAX.COM.AU The perfect battery for your EV, PHEV or HYBRID vehicle. Delivering reliable, environmentally friendly and safe power to start PHEV and... that one is for EVs, PHEVs and the like.
  15. Never seen that push button statement, that’s interesting. Can you please point me there? My battery is this: Lithiumax GEN 3 RESTART9 LCD 900CA ULTRA-LITE Engine Starter Battery | Lithiumax 2020 WWW.LITHIUMAX.COM.AU The all new Autosport International Award Winning Lithiumax RESTART9 LCD battery. Weighing just 3.9kg the NEW 3rd... That’s the manufacturer website. This does have a push button that’s there for 2 things, per the manual: 1. Press it and the voltage shows up in the LCD. 2. If the undervoltage protection is triggered, it shuts down and a button press wakes it with sufficient reserve to start the car. In this car, that would be fun, with a locked hood... @Silver_TT, twisties and pasteis de nata are a killer combination! 😂🤪
  16. Right, so out of curiosity, just emailed the manufacturer in Australia and they replied in about 30 seconds: "The RESTART9 is nominal 24Ah and 800CCA." Not toooooooo different from my guestimation.
  17. I was comparing the small lithium battery values in my bike its mfg published (real Ah vs "PbEq" Ah; CA and CCA) with the bigger lithium battery in my car, for which the mfg only published "PbEq" Ah and CA and since it's more or less apples to apples (LiFePO4 to LiFePO4) I was making an approximation to come up with possible missing values for the bigger battery. Given there's a relatively hight probability that the same Chinese manufacturer made the LiFePO4 cells in both (BYD, CATL, AVIC, etc), it's not too bad an assumption.
  18. They don't say. And don't even say what is the real Ah, they simply state 68Ah lead equivalent (PbEq, new term...) which is a common practice for lithium batteries manufacturers it seems. As a guide, my Skyrich lithium in my bike says it is a 6Ah, 360CA and 330CCA. The original AGM battery, dead after 2.5 years (a week after being taken off the tender, now sports 4.3V! Deader than the dead) was a 12Ah, 200CA. Interestingly, they claim it to be 21Ah PbEq. Doing the math, and assuming the proportion is the same, this would be: 68Ah PbEQ = 19.42Ah 900CA = 825 CCA Interestingly, all manufacturers for lithium batteries for bikes (where there's a huge offer and the market is very much alive) claim that a 4Ah (12Ah PbEq) 240CA is the equivalent to the original BMW 12Ah 200CA. Today I've driven the car in an errand, shut it down and turn it back on several times as in a normal day of use and all without a hiccup. The bike is the same, already for a few weeks. At rest, the Porsche battery is showing a consistent 13.30V and the bike 13.50V. I have Bluetooth battery monitors on both and they say 100% charge and do not come down. I don't know how they measure that but it's not based on voltage levels only, as I saw the previous batteries showing voltages above 12.4V but charges at 40% or so. Now, I only went the lithium way because around here I don't get below freezing temperatures ever (Lisbon). At the harshest winter nights it may go down to +5ºC, a couple of times a year, if I had serious cold here, I wouldn't go lithium. Brave new world of lithium.
  19. And here it is, already installed and working just fine: Looks awfully empty in there. I guess I have a little bit more of frunk space now 😉 The size comparison is amazing as well as the weight: 26kg the Bosch, 3.3kg the lithium. Considering that I replaced the comfort full electric seats with the 997GT2 seats, and saved about 40kg there, I managed to offset the weight of the Tip when compared with the manual 😉 Disclaimer: neither one of those mods was done to save weight, it's just a positive side-effect. I bought the Bosch about 5 years ago and it served me very well but it was no longer holding a charge and I had to have it on the tender overnight, going to sleep with 12.6 and waking up with 12.2 if off it. After a couple of days not running and off-tender, it was down to 12V. It was still starting ok but I guess it was a matter of time and as I hate being left stranded, decided to replace it. After having a look at all possibilities, Yuasa YBX9xxx, same-model Bosch (which is an AGM 95Ah 850A now) and top of the range Bosch S6, I ended up with lithium, after my excellent experience with my bike's lithium battery. With a nice Black Friday deal, I got this for about 600€, which is 3 times as much as a S5A13 and in the same price range as a S6 AGM. With the manufacturer states a duration of 3 to 5 times a lead acid. I hope so but don't really count on it: 15 to 25 years out of a starter battery? But let's see, battery duration is always a question mark, with the Porsche Moll ones never having lasted me more than 3 years and costing about half of this lithium.
  20. Thanks! Any specific recommendations to do this job? The Service Manual has nothing on this, except as a part of the engine removal/installation procedures as well as the torque specs. Also couldn't find any DIY on this, maybe I'll do one myself as I go along finding out how it can be done. I couldn't find out in the PET what are the nuts P/N that go with the strap and I normally replace nuts whenever I change old ones and I suspect these won't be in a good shape. Any idea?
  21. I have had electrical gremlins over the years, and have chased them in several different ways and frequently, things improved but then, occasionally they come back. The two specific gremlins are ABS/PSM lights coming on at warm idle and windows lowering on its own, car unlocking and interior lights turning on. I won't bother going through everything I have done chasing these things but the fact is that I just measured the voltage drop from alternator to body ground and I got 0.471V which is excessive. Also, cold start, I only have around 13.5V at the battery and it creeps downwards. I also have an alternator regulator coming for good measure since the battery is also dead/dying and the voltage at the battery, engine running fluctuates. That's cheap and easy to replace. Now, has anybody replaced their engine-to-body ground strap? If I remove the vacuum pump, oil filler neck and right intercooler hose, would I be able to get access to the strap's top nut to replace the thing or does this require an engine drop?
  22. Thanks, I did that, under load (i.e. during starting) and the MAX I saw in the voltmeter was 18 mV of voltage drop in the ground cable and 25mV in the + cable, which is obviously negligible. So I guess those cables are good. I got 14.10V cold in the jump points, just after start, whilst reading 14.00V in the battery. However, letting it run and warm up, both values went down slowly but surely and after 15min of idling I had 13.8 in the back and 13.6 in the front. When I turned on A/C at LO setting, headlights and rear window defroster it went down to 13.00V in the front. If I throttled up to 4000rpm (it's a Tip, it won't go above that whilst idling) I would get 13.72V in the front under those loads. I'm beginning to suspect that either the regulator or the alternator is going. Since the regulator is not expensive, I'll get a Bosch one and replace it to see what happens.
  23. Reading through the low voltage at the battery threads, I did notice that my bike used to have 13.8V engine running with the OEM AGM. With the lithium, it now has 14.6-14.7V, just bordering the maximum allowed by the battery of 15V. I suppose this is due to the different internal resistance and charging current. I’m curious to see if in the car the same is going to happen.
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