Mike D'Silva Posted 3February, 2015 Author Report Share Posted 3February, 2015 Thanks Peter.. I will keep the originals and get them fixed at some point... don't think its a job for me.. Would rather pay a pro to do a nice job on this. Today, I spent half the day in the garage, doing a job I was really dreading... changing the ballast resistors for the aircon and oil coolers.. These little ceramic resistors are mounted in the front fenders, attached to the oil cooler and aircon condensor radiator. Why change them? When the aircon is activated, the cooler fan would spool up to full speed, then turn off and cycle all the time.. this is not correct.. it should run at a slow speed.. this is apparently a tell tale sign of a bung ballast resistor. I knew this meant removing the front bumper.. so up on stands and away we go. This photo makes it look like the car exploded.. there's the oil cooler ballast resistor hiding.. This is the aircon one.. ive plugged in the new resistor, which you can see hanging.. i had to remove the fan and undo the bolts holding the radiator in place.. this isn't a hard job, but with all the crud, it is a dirty job. When I plugged the new resistor in, the fan would spool at low speed so it seems that it has fixed the problem. Time will tell... Link to comment Share on other sites More sharing options...
Tit Posted 3February, 2015 Report Share Posted 3February, 2015 Cool. I just learned something! Link to comment Share on other sites More sharing options...
Caledonian Posted 3February, 2015 Report Share Posted 3February, 2015 Mike, for a guy that not too long ago who was a bit unsure about taking your car apart, you have certainly embraced DIY maintenance Good informative posts too! Link to comment Share on other sites More sharing options...
hepkat63 Posted 3February, 2015 Report Share Posted 3February, 2015 well done ! I just had all the front of mine off - probably should have done that at the same time. Mine isn't broken (yet...) but I think it's one of those 'whilst your there' jobs Link to comment Share on other sites More sharing options...
Mike D'Silva Posted 7February, 2015 Author Report Share Posted 7February, 2015 Turns out one of my relays was "bung" too... they are located in the fuse box in the frunk compartment. They were $60 each from local Porsche dealer... the oil cooler fan and aircon fan use the same relay so I bought 2... I feel a little bit more comfortable knowing that the fan is spooling at the correct speed. Interestingly, on this page.. http://www.porschehvac.bergvill.com/, about half way down, I read the following... Condenser fan The Three-level pressure switch set the condenser cooling fan speed to high if needed. See above. The condenser cooling fan run at high speed if fed with 12V, and low speed is obtained by switching a power resistor/ballast (0.45Ohm) in series with the fan motor. Relay R14 contain the two relays for fan speed change. This resistor is mounted on the condenser, and is known to fail due to overheating and corrosion. Always fix a broken ballast resistor on the condenser fan, you don't want excessive pressure in you A/C system, it can cause leaks! Any refrigerant pressure faults will not be logged by the CCU since the pressure switches is directly connected to the compressor and condenser signals. The condenser blower motor operation is supervised and logged by the CCU. Air temperature at the centre dash nozzles shall be about 7-8degC with an ambient temperature about 20 degrees. Measure with A/C ON, resirculation ON and max fan. (or push the A/C max button on the 993) I've gotten the car re-gassed at work.. it is blowing nice and sort of cold (not as good as a modern car) so all I can do is monitor it. They did put some dye in as well, so I can go looking for leaks later... Link to comment Share on other sites More sharing options...
turboT Posted 4April, 2015 Report Share Posted 4April, 2015 Thanks for filling my early morning get up time with my 2 yr old. Some of these threads are better than novels! A great journey and a very interesting and amusing read. I noticed one question went ananswered in regards converting the tip to a manual. Was this something you have ever thought about doing? Link to comment Share on other sites More sharing options...
Mike D'Silva Posted 4April, 2015 Author Report Share Posted 4April, 2015 hi yes,.... i did think about it... contacted Autohaus as rumour has it they had done one before... But they said it was so expensive and complicated, they would never do it again.. Link to comment Share on other sites More sharing options...
D-banger Posted 4April, 2015 Report Share Posted 4April, 2015 hi yes,.... i did think about it... contacted Autohaus as rumour has it they had done one before... But they said it was so expensive and complicated, they would never do it again.. I have been told it is $20/25k to convert a 993. Back in the day a conversion from a sporto to manual was considered an upgrade. Link to comment Share on other sites More sharing options...
turboT Posted 4April, 2015 Report Share Posted 4April, 2015 hi yes,.... i did think about it... contacted Autohaus as rumour has it they had done one before... But they said it was so expensive and complicated, they would never do it again.. Maybe they meant from the perspective of the hours they would have to put in and finding a customer prepared to pay for it. You seem so handy on the tools and enjoy the time working on the car so probably not so much of an issue. Link to comment Share on other sites More sharing options...
JV911 Posted 6April, 2015 Report Share Posted 6April, 2015 I heard it was around $10k Link to comment Share on other sites More sharing options...
turboT Posted 7April, 2015 Report Share Posted 7April, 2015 I heard it was around $10k Or just get JV911 to do it for you for half price Link to comment Share on other sites More sharing options...
Mike D'Silva Posted 13April, 2015 Author Report Share Posted 13April, 2015 Well, last week was a week filled with frustration, dismay and depression.... Last Sunday, I backed the car out of the driveway, and when I shifted to D it jerked a bit and I assumed it was because I was too quick to change the shifter before the car had stopped completely. I parked the car as I was working on the other porsche and needed to put it in the garage. Later that day, I thought I'd go for a drive in the 964 but it was pulling like a dog.. and I realised that the manual shifter wouldn't shift... the light wouldn't light up. Pulled over, turned it off, started it again = no difference.. driving like a slug. So my car is in limp home mode... fun. After I took the other car back to hide in its weekly location, I put the 964 back in the garage and started to sulk. Seems there are a few threads on various forums that show a similar problem.. others say there are "jumpers" that need to be bridged, or bad connections, or flat batteries... I had an obd cable and used a downloaded version of durametric software, and the only error I got was "21 - rpm signal"... This was from the tiptronic ecu. Try googling that... SFA available... If you download the service manual for the tiptronic, it shows a whole range of tests in a slightly different language. k line, o line, pin 3, oscilloscope... sine wave.. ?? I spent all Easter Sunday and Monday googling, reading, downloading etc.. I couldn't check the DME for error codes since my cable wouldnt connect to it.. so I had to borrow Ken's cable for the Scantool program. But his scantool wouldn't read the Tiptronic... dunno why but we had tried it in the past also without success. Removed the passenger seat (after removing the driver seat incorrectly) to make sure the ecu was still plugged in (of course it was). Tried resetting by disconnecting the battery.. Tried disconnecting the ecu... The clock in the 964 is blamed for all problems under the sun.. I checked all the connections... couple of the globes were blown so I changed them.. now my tiptronic warning lamp works! and is permanently on.. effin sensational. And the light next to the number 3 (3rd gear) on the dash was flashing! One forum thread suggested that the microswitches under the shifter could be fouled... continuity tester confirmed all switches working.. damn... Another thread said there was a throttle position sensor in the engine bay that was prone to failure.. surely wiggling the connector will fix my problem.. nope. I couldn't wait to go back to work on tuesday since it would force me to walk away from the stupid car. Luckily, I met a new friend on another forum who came over with his wiring diagrams, oscilloscope and 35 years of knowledge. WE (ok, i watched) confirmed that the rpm signal was indeed leaving the DME (engine ecu) and was making its way through the harness, to the tiptronic ecu plug... which means that the most likely diagnosis was that the ecu was stuffed.... Call Porsche Aus.... $3000........ Hang up... Find a second hand one....much more palatable but still annoying as hell. It turned up today, and I nervously plugged it in... Turn the key and all the warning lights are on..... Deep breathe, start the engine... and all lights are out! Car goes into manual mode and drives like a champion. In fact, now it drives better than before. Shifts are faster, and the kickdown is awesome! My theory is that my old ecu might have been faulty from the beginning.. or at least from when I got it.. as the car is a much nicer driving experience now. Guess I won't sell it just yet... Link to comment Share on other sites More sharing options...
turboT Posted 13April, 2015 Report Share Posted 13April, 2015 Well, last week was a week filled with frustration, dismay and depression.... Last Sunday, I backed the car out of the driveway, and when I shifted to D it jerked a bit and I assumed it was because I was too quick to change the shifter before the car had stopped completely. I parked the car as I was working on the other porsche and needed to put it in the garage. Later that day, I thought I'd go for a drive in the 964 but it was pulling like a dog.. and I realised that the manual shifter wouldn't shift... the light wouldn't light up. Pulled over, turned it off, started it again = no difference.. driving like a slug. So my car is in limp home mode... fun. After I took the other car back to hide in its weekly location, I put the 964 back in the garage and started to sulk. Seems there are a few threads on various forums that show a similar problem.. others say there are "jumpers" that need to be bridged, or bad connections, or flat batteries... I had an obd cable and used a downloaded version of durametric software, and the only error I got was "21 - rpm signal"... This was from the tiptronic ecu. Try googling that... SFA available... If you download the service manual for the tiptronic, it shows a whole range of tests in a slightly different language. k line, o line, pin 3, oscilloscope... sine wave.. ?? I spent all Easter Sunday and Monday googling, reading, downloading etc.. I couldn't check the DME for error codes since my cable wouldnt connect to it.. so I had to borrow Ken's cable for the Scantool program. But his scantool wouldn't read the Tiptronic... dunno why but we had tried it in the past also without success. Removed the passenger seat (after removing the driver seat incorrectly) to make sure the ecu was still plugged in (of course it was). Tried resetting by disconnecting the battery.. Tried disconnecting the ecu... The clock in the 964 is blamed for all problems under the sun.. I checked all the connections... couple of the globes were blown so I changed them.. now my tiptronic warning lamp works! and is permanently on.. effin sensational. And the light next to the number 3 (3rd gear) on the dash was flashing! One forum thread suggested that the microswitches under the shifter could be fouled... continuity tester confirmed all switches working.. damn... Another thread said there was a throttle position sensor in the engine bay that was prone to failure.. surely wiggling the connector will fix my problem.. nope. I couldn't wait to go back to work on tuesday since it would force me to walk away from the stupid car. Luckily, I met a new friend on another forum who came over with his wiring diagrams, oscilloscope and 35 years of knowledge. WE (ok, i watched) confirmed that the rpm signal was indeed leaving the DME (engine ecu) and was making its way through the harness, to the tiptronic ecu plug... which means that the most likely diagnosis was that the ecu was stuffed.... Call Porsche Aus.... $3000........ Hang up... Find a second hand one....much more palatable but still annoying as hell. It turned up today, and I nervously plugged it in... Turn the key and all the warning lights are on..... Deep breathe, start the engine... and all lights are out! Car goes into manual mode and drives like a champion. In fact, now it drives better than before. Shifts are faster, and the kickdown is awesome! My theory is that my old ecu might have been faulty from the beginning.. or at least from when I got it.. as the car is a much nicer driving experience now. Guess I won't sell it just yet... you won't be needing my gear box now then? Link to comment Share on other sites More sharing options...
Mike D'Silva Posted 13April, 2015 Author Report Share Posted 13April, 2015 i still want it... Link to comment Share on other sites More sharing options...
Peter M Posted 13April, 2015 Report Share Posted 13April, 2015 Well, last week was a week filled with frustration, dismay and depression.... Last Sunday, I backed the car out of the driveway, and when I shifted to D it jerked a bit and I assumed it was because I was too quick to change the shifter before the car had stopped completely. I parked the car as I was working on the other Porsche.... Quick double take! WHAT DO YOU MEAN "..the other PORSCHE"!!! Spill your guts Mr D'Silva! Good work with the ECU BTW. Link to comment Share on other sites More sharing options...
hepkat63 Posted 13April, 2015 Report Share Posted 13April, 2015 how much did you find a 2nd hand ECU for ? Was this the motoronic ECU you replaced? Pictures? Part number? Interested in case it ever happens to me !! (fingers crossed). Link to comment Share on other sites More sharing options...
hugh Posted 13April, 2015 Report Share Posted 13April, 2015 Quick double take! WHAT DO YOU MEAN "..the other PORSCHE"!!! Spill your guts Mr D'Silva! Good work with the ECU BTW. bump Link to comment Share on other sites More sharing options...
Mike D'Silva Posted 14April, 2015 Author Report Share Posted 14April, 2015 how much did you find a 2nd hand ECU for ? Was this the motoronic ECU you replaced? Pictures? Part number? Interested in case it ever happens to me !! (fingers crossed). ebay... $550... it was the ecu for the tiptronic, not the engine ecu... it lives under the passenger seat... Link to comment Share on other sites More sharing options...
baso Posted 14April, 2015 Report Share Posted 14April, 2015 but you have avoided the most important question - what is the new ride?! Link to comment Share on other sites More sharing options...
ByronBayChris Posted 14April, 2015 Report Share Posted 14April, 2015 Are you making it a 6 or leaving it a 4? Link to comment Share on other sites More sharing options...
hepkat63 Posted 14April, 2015 Report Share Posted 14April, 2015 ebay... $550... it was the ecu for the tiptronic, not the engine ecu... it lives under the passenger seat... thanks Mike - nice to know. Will print and file Link to comment Share on other sites More sharing options...
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