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jmj996

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Posts posted by jmj996

  1. Well, I decided to take a shot and simply add more refrigerant, and it worked.  So much for a methodical approach using gauges and Porsche A/C system guidance.  Porsche's charts indicating that it should have a low-side pressure of 20-24psi were just far too low for my car.  I was continuing my research this weekend and found a post from a mechanic saying that he usually charges the low side up to 40psi (referring specifically the 996 and 986), so I decided to add enough refrigerant to bring the pressure up from 30psi to 40psi, and surprisingly, it took an entire 940gram to do it, which is the specified amount of refrigerant required to fill an empty system.  Now it's blowing very cold!  And, the high-side pressure is around 240, which is within range according to the chart.

     

    So, lesson learned, 30psi is practically nothing in these cars, and the Porsche chart for low and high-side pressure is way too low.  30psi was enough pressure for the compressor to kick and stay on, but it was not indicative of having enough refrigerant to cool the evaporator.

     

    I suppose it's possible that the low-side gauge on my A/C hoses is not correct, but it's a nice set from Harbor Freight, so I doubt those are the problem.

  2. Let's try a few simpler questions:

    1) If you've ever had a clogged A/C system, what was the culprit?  I've seen an example on YouTube of somebody's A/C lines underneath the car getting crimped nearly shut, but haven't found anything else.  I've read anecdotal info about how leak sealer can cause a clog, but haven't seen any first-person explanations of something that was clogged because of it.

    2) Have you ever needed to have an A/C expansion valve replaced?  If so, what were the symptoms that led to its replacement?  Obviously there a lot of these that need to be replaced, because they're available (in stock for this MY) on all of the major parts sites.

    3) Have you ever had to replace anything in the A/C system (besides the compressor) due to something other than leaking or physical external damage?

  3. Hello all, looking for your help diagnosing A/C issues. It's summertime in Peru and temps are already in the 80's in Lima, so I really need my A/C on my 1999 996 cabriolet.  It hasn't worked properly for about three years.  It does make the air somewhat cooler when I turn it on, but nowhere near cold. 

     

    The strange thing is that it's not necessarily low on R134.  The pressure gauges show that the low and high sides are both around 70psi when the car is off.  When the car is on and A/C is turned on, the low side drops to 30psi, but the high side never increases - it doesn't move at all.  When the car is running and the A/C compressor is switched off, the pressure jumps up to 55psi.  Then, after turning off the engine, it's back to 70-75psi.  According to the Porsche manual, the low-side pressure should between 20-24 psi (regardless of outdoor air temp), and when the car is running at 26 degrees celsius outdoor temps, (it's cooler this evening), the high-pressure side should be between 10-17 bar, or 145psi to 246psi.

     

    The compressor is definitely running, and the radiator condenser fans are running.  The only other symptoms are:

    1) I hear a slight hissing noise in the dash area when I turn on the A/C.  It starts out as a high-pitched hiss, and slowly goes away within about ten seconds.

    2) I had the usual foam degradation on the air diverter doors and haven't really done anything about it - but from what I understand, it wouldn't have this serious of an impact, and from what I've read, the foam degradation usually affects the ability to heat the car.  I can't be 100% sure that the flaps are actually moving when they're supposed to, but I can confirm that when I select the recirculation button, it works correctly because I no longer.  Regardless, the main problem is evident in the fact that the high-side pressure doesn't move.

     

    The last time I recharged the A/C (just a little low), in the summer of 2020 (in the northern hemisphere), it worked fine, then we moved to Peru and it continued working through the Peruvian summer from January through May of 2021.  It has not worked properly since.

     

    I can only think of a few reasons that the high-side pressure won't increase:

    1) The A/C compressor isn't coming on, or isn't working.  I know it's coming on - I can see it spinning, and the idle definitely changes exactly as expected when turning it on or off.

    2) The expansion valve is (badly clogged). I'm not sure about this one, but the fact that it's hissing a little bit when the A/C is turned on, and the fact that the high-side pressure never changes, leads me to believe that this is possible.

     

    Any ideas?  Has anyone seen this before?  Thanks in advance!

     

     

  4. I just installed the PCCM Plus today into my 1999 996 cab, and it's awesome! If there's one main thing I've learned while researching this process and performing the installation that I'd share with others that are thinking about doing this, it's that there are major differences between different cars depending on years and options, so no single installation procedure or video is going to have all the necessary details for everyone (unless you're really lucky and the video happens to show a car with the exact same configuration).  You will need to do your research to determine what parts need to be installed, and what modifications (or in some cases, new parts and adapter cables) are required.

     

    All things considered, I probably had the easiest path, mainly due to the following:

    1) Basic 4-speaker system - no Bose (so, no amplifier), no MOST connections

    2) On the 99 with a DIN-1 system (the CDR-220), the original factory brackets can be easily modified to accept the PCCM Plus (a Dremel made this much easier).

    As a result, I didn't need any of the adapter cables or replacement brackets that aren't included with the standard kit.

     

    Two brackets that had to be modified on my car are the main plastic support bracket (sometimes referred to as the 'horseshoe') and the rear metal bracket.  I've attached a PDF that shows pictures with the areas that had to be modified.

     

    For the plastic support bracket, I had to modify five areas - trim three sections on each side, remove the center bar, and drill holes in the sides.

    a) The upper mounting holes for the original climate control mount had to be trimmed.

    b) There was a small plastic guide for the climate controls.  It protruded forward from the support bracket further than the other surfaces, so I had to trim a little off of that.

    c) The lower mounting holes for the climate controls had to be trimmed.

    d) The horizontal crossbar had to be removed.

    e) The side mounting brackets that come with the PCCM Plus didn't have anything to squeeze on the upper section of the main plastic mounting bracket to hold the radio on (the lower section was fine).  So, I had to drill holes in the side and put bolts through the holes to hold the mounting bracket to the upper plastic area.  This made it very solid.

     

    The rear metal bracket only needed one slight modification - to drill out two rivets on each side to remove the dark metal clamping brackets.

     

    Some other notes/observations:

    1) I did not install the microphone in the suggested location.  I removed the supplied microphone from its housing and installed it in the factory-intended location to the left of the gauge cluster (see the attached PDF).  This required removing the gauge cluster, but otherwise it was not difficult.  The new microphone squeezes into the original microphone mount quite nicely.  To route the wires in a clean way, I had to remove the wires from the white connector for the stereo, slide the wires through a very small opening next to the screw hole that holds the gauge cluster to the dash, and then run the wires within the gauge cluster housing to the right side of the gauge cluster.  That put them in a perfect position to feed into the back of the dash and over to the center of the dash.

    2) I did not install the media box (with USB and AUX connectors) in the storage tray, or in any visible location.  I have a storage tray in the third slot down, above where the climate controls were installed, but I didn't want it filled up with this box, so I just left the box sitting in the lower back area of the center console, immediately behind the carpeted trim piece on the passenger side.  I have a long USB cable connected to it that comes out under the carpet trim piece, and if I ever need to replace it, it's easy to access by simply removing the carpeted trim piece.  This keeps this ugly, nonstandard media box out of site, and also makes the installation of the stereo much easier because the connector wires for the PCCM plus are much closer to the stereo.  If you've watched some of the installation videos, one of the biggest problems people have is with connecting the cables for the media box, because they're so short (limited by Porsche due to maximum allowable length to prevent signal dropoff).  I had no problem at all with connecting any of the wires.

    3) I did not install the MOST control unit at all, I left it in the box.  As mentioned above, this is not needed in cars that don't have MOST, and it's best not to even plug it in or the PCCM Plus will get confused, thinking it needs to send the signals to the MOST control unit.

    4) I was able to transfer my output (line out) connector from my CDR-220 directly to the PCCM Plus, so my under-seat powered subwoofer still works.  I did have to switch the volume output settings in the PCCM Plus from CAN to AMP in order for it to send the signal to the output connector.

    5) Step 3.1 of the installation procedure did not apply to my car.  I simply attached the antenna cable adapter included with the kit (goes behind the stereo between the original antenna cable and the PCCM Plus), and the antenna worked great.

    6) After the installation, the horn would honk once when I locked the car. Some quick Internet research shows that there is a ground wire attached to a bracket on the left side of the plastic support bracket that causes this.  When you no longer have the original factory radio, this wire has to be disconnected, or the car will register a missing stereo code.  Fortunately this wire is accessible by simply removing the left trim piece, so I just knocked it off the connector and the problem went away.  If I knew this before the installation, I would have just left that grounding bracket off and taped off the wire.

    1999 996 PCCM Plus pics.pdf

    • Like 1
    • Upvote 1
  5. Thanks for this info.  I've received my PCCM Plus and and preparing for the installation in my 1999 996 cab.  I only have the basic CDR-220 with four speakers (don't have either CAN or MOST, nor do I have a CD-changer or Bose system), so it appears I have the simplest path. 

     

    I'm looking at the Porsche installation instructions hosted at NHTSA.gov. Due to a lot of different 996 stereo options over the years, (not to mention the switch to MOST), you have to figure out which parts of the instructions apply to your vehicle. They're not very good at outlining what should or should not be done in my specific case, but thanks to @Larsinexile at least I can see that I don't even need to install the MOST control unit, so I probably won't install the black metal tray either, in order to provide better ventilation to the stereo.

     

    I have one part that I need help clarifying - it's about the antenna line. Step 3.1 on page 5 shows a procedure to bypass the antenna amplifier, and it says this should be done on all vehicles without M440. Does this apply to US/CAN vehicles?

     

    My initial impression is that this step does not apply to US vehicles because Step 3.1 requires the use of the adapter shown on page 3, identified as item 10, but this cable is not in the US kit (and neither are some other ROW parts like the DAB adapter).  The procedure says that this car's antenna should be disconnected from the amplifier and connected to this long antenna cable, which should then be run to the back of the stereo.  Did anyone else receive this long antenna cable?  Has anyone else with a US/CAN vehicle done procedure 3.1?  If so, did you already have PCM in your car?  I've gone through all of the cables supplied with it (US model) and the only antenna-related cable is an adapter for the standard antenna wire to the back of the stereo. The procedure doesn't even show this being connected (which is fine, it's almost too simple to bother mentioning), but it seems to me that step 3.1 should be split into an 'a' and 'b' depending on whether it's a US antenna or ROW antenna.

     

    I found a video showing this process at 9:17 in the video, but this is a UK/ROW car, and it originally had PCM.

    • Like 1
  6. 8 hours ago, DGI said:

    Thats precisely the conclusion ive come to in my research. Engine has to come down for maintenance anyway. Assuming the RMS/ IMS is dry when that happens, its not getting replaced 

    119k on a 20-yr old car implies that it was not exactly a daily driver.  If you don't have any history on it, assume that at some point in its life, it sat for weeks at a time - possibly longer.

     

    Hopefully you'll have a good mechanic advising you on this.  They won't really know the condition of the bearing unless they remove that outer plate and take a look.  The condition of the outer seal is not the end of the discussion.  It could have been replaced in conjunction with a clutch replacement.  The condition of the seal on the bearing itself is your first step to determining if the bearing is still viable, and even then, you don't really know unless you pop off the bearing seal (which is irreversible), so it's a catch-22.  My mechanic removes the bearing seal on all Porsche engines with an IMS and relies on engine oil lubrication, and he says he's never had a failure.  He's been working on these engines since the 996 was first being raced in the late 90's. 


    They should also change the water pump as preventive maintenance if you have no maintenance history on it.  A water pump failure is a disaster in these cars because the impeller is plastic and it gets chewed up against the block because when the water pump bearing fails, the axis of the pump shaft is no longer perpendicular to the block.  The result is that little bits of plastic end up getting circulated through the coolant system as it's failing, which results in these bits entering the cylinder heads and sometimes getting caught in the small passages, creating hot spots that crack the head.

     

    Good luck!

  7. I've been experiencing these codes for a while too. I have new pre-CAT O2 sensors (within the last year anyway) and I can hear the pump coming on, so that doesn't appear to be the problem, but it occurred to me as I read your post that your codes appear to take much longer to come back than mine. Since everything else seems to check out, I wonder if you're experiencing intermittent pump relay problems? On my 951, when my headlight relay started to go out, it would work sometimes, and not others. It went on for over a year this way before it finally created a real problem for me and I tracked down the source of it. An interimittently-functioning relay would make reproducing the problem on demand very difficult.

  8. Koni FSD's (just now available for the 996) from Paragon Products are on the way. I decided not to buy replacement springs yet, I'm going to install these and measure everything per the factory manual. I will probably also swap the LR and RR springs (assuming they are identical) to see if that has an impact. Really looking forward to driving the car with these. I have great highways for the daily commute, but the last five minutes to my house off the highway is just ridiculous (that's just Naples - it's like that here). Also, the salesperson said he had an opportunity to test drive cars with these at a Koni factory test center. One of the interesting aspects he mentioned is that cars fitted with FSD shocks/struts did not kick in the PASM as much as the cars that had factory struts & shocks, seeming to validate that these allow the car to keep a better handle on the road. Probably not a good solution for the track because you wouldn't always know exactly how the car is going to react at the limit, but they seem ideal for a daily driver.

    From the web site:

    -----------------------

    Frequency Selective Damping

    The first shock absorber offering superior road-holding without compromising comfort.

    Koni introduces FSD, the first no-compromise shock absorber in the world. A revolutionary new technique which combines the benefits of firm and comfortable suspension in a single perfect shock absorber. Firm for sporty driving on even road surfaces. Comfortable for a smooth ride on uneven road surfaces.

    Realizing the seemingly impossible! Two characteristics that seemed diametrically- opposed, proved to be a source of inspiration for specialists from KONI. Following lengthy development and testing, the ultimate solution was reached: KONI FSD - Frequency Selective Damping. A revolutionary new technique whereby the benefits of both types of ride characteristics are combined in one perfect shock absorber. Banishing the disadvantages of the past. FSD shock absorbers; a smart suspension system adjusting automatically to road conditions as well as driving style. And all of this in a fraction of a second. FSD guarantees greater stability, greater control and thus greater driving pleasure.

  9. I run spacers with the longer lug bolts as well. I can't attest to how much of an impact it makes with any real data, but I do want to add something that I learned from a dealer, because I don't see this written about the use of spacers very much: I was told that the reason there is so much space between the outer edge of the wheel and the fender lip, as the car comes from the factory, is to allow for the use of factory snow chains (look them up - they're available from Porsche as a factory accessory). The extra space doesn't have anything to do with any perfect engineering scenario, it's about allowing the space necessary to use the chains, so before the spacer-haters start chiming in I want to throw that out.

    Text from a Porsche snow chain product available online:

    Special low-profile design with fine-link chain for minimal adhesion of ice and snow, these chains are easy to fit. Note: Cannot be fitted to vehicles with spacers.

    Seems to provide further clarification that the spacing from the factory is simply to allow for snow chains.

  10. This sounds like the kind of thing I would do, so I wouldn't shy away from that at all. If the factory transmission doesn't even hold up for 100k miles, why have it fixed or replace it with one exactly like it? It would be very expensive and is obviously not that strong (or maybe it had a previous owner that couldn't drive a stick very well). I would also spend a few more $$ and upgrade like this owner did.

    I'm at around 55k right now. Don't have any issues with the tranny at all, but I have had head seals replaced at around 38k miles, the clutch, RMS and IMS replaced at 45k, and the RMS was replaced twice before that by a previous owner. The third RMS change wasn't actually necessary. I just ordered the parts because I was having the clutch replaced anyway and wasn't sure if the RMS was the revised version (or installed with the revised tool, I don't remember what was revised). The dealer said the existing RMS actually wasn't bad, just sweating a little bit of oil that probably wouldn't even show up on the ground.

    There are other common repairs that shouldn't concern you - window regulators, coolant tank, radio, seat belt parts, etc.

    I'm curious if the rear struts have been changed on that car yet. At 55k miles, my left rear sags AND feels fishy, like a bad strut, and I've read (though I cannot speak for the accuracy of the sources) that the one-sided sagging is not uncommon. Measure the rear fender heights on each side to get a rough idea.

  11. You might be experiencing a problem with the interior sensors faulting and setting off the alarm - that was the case with my 99 Boxster that was going off in the middle of the night at least once a week. The dealer advised me to double-click (hold...release.hold...) the lock/alarm - what this does is lock the car, but only set the alarm on the doors, disabling any interior sensors. When you correctly double-click the alarm, you will hear a single honk from the alarm horn. Once I started doing this, the alarm never went off on its own anymore.

  12. :welcome:

    If the water pump was recently replaced then it is likely they didn't get all the air out of the system.

    It will self bleed the air out but you should top up (to the Max mark) every few days until it stops dropping.

    Is that dealer close to you? I'd bet that the dealer who replaced the water pump will top it off for you for free - one because they swapped the pump, but two, to probably try to establish some good will and make you a customer.

    Beautiful car! Good luck with it!

  13. How much time/how many miles have you given it? I have found that some tires, especially softer compounds, need a 'break-in' period to match the characteristics of the used tire. I know your other tire wasn't used much, but it was certainly past the break-in period. One way to know if the traction is substantially different is to force the ABS to kick in. See if it kicks in on the used tire before it kicks in on the new tire.

    Also, check the serial numbers on both tires and see if the manufacturing date was substantially different (don't recall exactly, but I think the last four numbers correlate to the year and month of manufacture). The tires could actually be significantly different, even if they are the same manufacturer/model.

  14. Good topic. I have the airbag light right now as well (as well as a CEL that I need to diagnose), just ordered the Durametric.

    You'll love it. I'm a closet geek - so I love this thing.

    Check out my post here

    http://www.renntech.org/forums/index.php?showtopic=30198

    I'm already out of the geek closet. Switched to IS/IT work years ago, forgoing a reputation I spent all my college years building. Oh well. Got the Durametric in this week and started playing on Thanksgiving. Pretty easy stuff, though I have codes P1123 and P1125 and for some reason the Durametric does not have the text for code P1123, had to come here to get that. Regarding the air bag light - confirmed that I have the same issue as this thread, I have BOTH the 45 and 48 codes for the seat belts. Looks like I have some cleaning to do...

    9X6 Airbag Selected

    About to get fault codes

    moduleType = AirbagB05

    DTC Count = 2

    Fault Number:48

    Description:Belt buckle passenger

    DTC Count = 2

    Fault Number:45

    Description:Belt buckle driver

  15. I checked their web site. Though they have a 'race' wheel section, it just appears to be a product line name, not a true application category. Most of their stuff looks kind of 'blingy', not like serious performance folks, more like serious 'pimp your ride' folks.

    You should be looking for LIGHT, cheap (read: easily replaceable) and proven wheels for your track days - and I would even suggest looking more closely at 17" wheels for a few reasons - tires are cheaper and you're less likely to ruin a wheel in the event of a rough curbing event. There are plenty of good used (and attractively priced) Porsche OEM 17" and 18" wheels out there on eBay and Craigslist that would suit your needs - especially the hollow spoke wheels (though those are 18" 's). You can't get better than this for track days on a 996 unless you spend big $$$$ for true performance wheels.

  16. As far as I know, you cannot. The reason is that Porsche has already configured the alarm to beep once in certain circumstances - the one described above (where something is left open - in my case I have heard it when I haven't fully closed the front trunk, etc.), and the other situation I'm aware of is when you intentionally disarm the interior motion sensors. In order to intentionally disarm the interior motion sensors, you have to double-click the alarm (hold...lift.hold...) or alternatively using the key in the door, turn...center.turn.... This still sets the alarm for the doors, but inactivates the interior motion sensors, and the Porsche alarm provides you with confirmation of this by honking the horn once (at least on a 1999). I also owned a 1999 Boxster, and it exhibited exactly the same behavior. I had to begin using this feature on our Boxster because the alarm would go off in the middle of the night once every couple weeks. It really pissed off the neighbors. Finally, inactivating the interior motion sensor took care of that problem.

  17. I just picked up my tip 99c2 cab from getting two new rear potenzas.. when I started the car, some strange sound came of the engine... clank clank clank, and it would increase with more throttle. I turned of the car and restarted it... the noise went away.

    But, when driving home around 30 miles /h the engine light came on, and white smoke started coming of the left exhaust.. a lot of smoke, and more when i pushed the throttle.

    I drove it for about a mile (i live close to the tire place) and parked it in my garage. The smoke has a light burned smell, of course.

    I read several causes throughout the forums and nothing looks good at all. car has 108,000 miles, never a problem.

    So, before I take to the mechanic, what am I looking at? Thanks for your help.

    I'm really sorry to hear that. I plan to keep my 99c2cab for the long term, and from all the stories I read on Rennlist I feel like I am bound to run into something like this someday. But at least I feel that if I put a new (updated) Porsche engine in it, I should be in great shape from then on.

    Do you trust the tire shop? Any chance they took it for a joyride? You should have a mechanic examine the log in the computer to see if anyone redlined it.

    I strongly recommend that you do not try to start the engine again - unless you can pull the plugs and crank it over first. If you do have coolant leaking into one of the cylinders, you could damage internal engine parts very quickly because coolant will not compress like air. Also, if you can pull the plugs on the left bank, you might see one that looks very different. If so, then you know a teardown is in order, and then most likely a replacement engine.

  18. Not sure about your tire sizes as I have 17" wheels, but from your description, it sounds like it's an alignment issue. You have a type of alignment used for track/DE events - either little or no toe-in. See if you can measure your toe-in yourself and start from there.

    At those speeds, you will want more front downforce as well - for your comfort level, at least get a GT3 spoiler lip or swap out the entire front bumper cover for a GT3 or aftermarket bumper cover.

  19. You could do just about anything here - it depends on how far you want to go. I actually installed a Porsche (Becker) CDR-220 from the 986/996 series into my 1986 951, and I have Infinity speakers (component up front, 2-way in the rear) plus a subwoofer in the back powered by an AMP that's installed under the dash on the passenger side. This is not a very special or aggressive setup, it's pretty vanilla. Really nice to have an updated, yet clean factory look with the Porsche head unit, but still get the CD player, Auxiliary input (which I use to attach an iPod via headphone jack cable) and auxiliary output (which I run to an amp for a subwoofer). I'm going to replace that stupid gauge panel installed below the radio by the previous owner with the original storage cubby, and get the a-pillar gauge panel instead.

    You have the ability to install a double-DIN radio, so really, you can do anything depending on how much you want to spend, including in-dash NAV systems with large screens. Speaker options are somewhat limited unless you buy aftermarket door speaker mounting plates. With this car you really need a component speaker system (with crossover included) up front, so that you can mount the tweeters up high and just go with woofers in the door, but that will require aftermarket speaker mounting plates. They may add a bit to the cost, but will allow you to avoid installing subwoofers in the back (assuming you don't need a booming system) because you can run decent subs in the doors.

    post-8562-1258145670_thumb.jpg

  20. I'm curious if the European spec 996's originally came with the Mobil1 0W-40 recommended as NA spec cars do.

    Wish I had read this thread earlier. Found a great deal on Mobil1 0W-40 at a military exchange a few months ago and stocked up on two oil changes worth of oil. But where I live now, I think I should have gone with 5W-40 at a minimum. Only 56k on the engine, so hopefully 0W-40 is fine for now.

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