Jump to content

Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must log in to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings (limited)
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • View Reviews
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)


  • Content Count

  • Donations

  • Joined

  • Last visited

  • Days Won


Posts posted by JFP in PA

  1. 36 minutes ago, Vtx531 said:

    Yes, pulled thermostat and tested good. I have the paperwork from the water pump. It says 42579 which comes up at Gates brand when I do a google search. The photo shows metal impeller but people are “complaining” in the reviews that it is plastic, so who knows... hopefully composite?


    I drained and vacuum filled the system again. Same result. No heat. I also “flushed” the radiator hoses and heater hoses while they were off with a garden hose and there seemed to be no obstuctions.


    Water pump and thermostat were replaced because of previous owner overheating.


    Attached is a photo of the bucket that I filled and how much water it sucked in with the vacuum.


    New radiator cap should be here in a couple days but I don’t think that would affect the issue with no heat.



    I believe the Gates pump has a metal impeller:



    I am concerned that the pump was replaced because of overheating, not because the pump had failed or was making noise.  The question is why was it overheating?  At this juncture, if the car was in my shop, I would pull the water pump and look at both the impeller and the wall of the engine case.  If the case is tore up, you are chasing your tail trying to get the system to work.  As for the reviews of the pump, some "complain" the impeller is composite, others complain it is metal, so it sounds like they could go either way.  In any case, we ONLY use the factory water pumps, which are all composite impellers, and work well, unlike several aftermarket brands we have looked at.  Unfortunately, many aftermarket bits for Porsches are really junk; water pumps, surge tanks, and AOS units are great examples of what not to buy.  We have seen several fail right out of the box.  Yes, they are a few bucks cheaper, but after some people have gone through two or three units in quick succession, that few bucks looks like a really bad deal...…..

  2. Something 'organic" is wrong here, so let's start with the basic elements of the system:


    You said you pulled the thermostat and tested it, correct?


    Do you have the paper work from the water pump install?  Can you see the water pump and verify that it is new?  Is it possible to contact the shop that did the work and find out why they replaced the pump and if the original and replacement pump had a metal or composite impeller?


    People have a tendency to replace the composite impeller pumps in these cars with aftermarket metal impeller pumps because they are cheaper and people think they are better, which is a big problem.  The clearance between the back of the impeller and the engine case is only a couple thousandth's of an inch in order to get proper coolant flow, and Porsche used composite impellers specifically because as the pumps age, the shaft begins to wobble and the impeller hits the engine case.  If the impeller is composite, the impeller breaks up and fails; if the impeller is metal however, it begins machining away the engine case, creating a much larger gap, and renders any new pump, regardless of impeller type, unable to move the coolant in sufficient volume to keep the engine cool.  Unfortunately, there is no coming back from this a the engine would have to come out and apart to spray weld up the are and then be machined to the correct tolerance's, which is too expensive to be realistic.

  3. 3 minutes ago, Vtx531 said:

    Maybe there was something wrong in my procedure, here is what I did:


    1. Remove two large hoses, two small hoses (heater core?), drain plug (nothing came out the drain plug at the end).


    2. Reconnect all hoses and drain plug.


    3. Vacuum system down to 25.5”. Let it sit for 5 mins, verified no drop(rise?) in vacuum pressure.


    4. Allow the water to be sucked in from a 5 gallon bucket


    Something I am missing??


    Sounds correct, but obviously if you have no heat from a heater that has full flow all the time, there has to be air in the system, or the doors on the HVAC system are not moving correctly.


    Pull the cover off on the passenger's side next to the battery, start the car and let it warm up, you should be able to feel both heater lines and see if they get hot.

  4. 4 minutes ago, Vtx531 said:

    Vacuum fill seemed successful (or so I thought). When I put 15 psi pressure into it to test, the level still decreased slightly but not nearly as much. Not sure how there could be any air in the system. I took it down to 25.5” and it was holding steady.


    I drove for a few miles, temp seemed pretty steady at 180 degrees and I thought the issue was fixed, but as I pulled back into my driveway, temp began to rise (slightly) to just above 180. I popped the trunk and could hear what sounded like boiling/gurgling coming from the cap area but it didnt flow over and no steam.


    I am using distilled water until I get this figured out. Could that be having any effect?


    Weird thing is now the heater seems to not work at all. Before the vacuum fill, it got warm but not hot.


    Distilled water will not change anything.


    If you don't have heat, you still have air in the system.

  5. Just be aware of two points:


    1. You are disabling a federally mandated safety item; in many states that is grounds for failing the car at its annual inspection.
    2. Your insurance company can play games with you if you have an accident such as rear ending someone of bumping into an inanimate object.  You purposely disabled a mandated safety feature designed to prevent such things, you could end up on the hook for all the damage.

  6. 15 minutes ago, Vtx531 said:

    I was using a hand pump vacuum so the vacuum pressure was definitely coming up SLOWLY. It seemed less like burping and more like drawing up/out the fluid in the tank.


    That's because you have a lot of air in the system. Try draining the tank with a turkey baster and then pulling a vacuum SLOWLY...…..

  7. 1 minute ago, Vtx531 said:

    Coolant level still goes down when I pressurize the system so I think that means there is still air? I probably need to drain the whole thing, then pull the vacuum and then refill. I don’t understand how it would work if there is already air trapped.


    We do this all the time when DIY coolant changes don't work out; it can be done, but you have to raise the vacuum level slowly in stages to allow the air to come out.

  8. 7 minutes ago, Vtx531 said:

    Using my makeshift vacuum fill system. When I bring the vacuum pressure up, the coolant level in the expansion tank rises. At about 15”hg the coolant starts getting sucked up the hose. If I release th vacuum, coolant level goes back down to where it started. Is that how it is supposed to work if it is already partially filled?


    I did it a second time and it did pull in coolant...all the way to the top of the filler neck.


    Not sure if I did the procedure correctly. It seems like if there was an air pocket in the system that is already filled then the vacuum would just move the air pocket closer to the filler hole with the coolant level rising a corespondent amount. Without actually getting the air pocket out.


    You need to throttle the vacuum and bring the level up slowly, the system is trying to "burp" and you need to bring the vacuum up in stages so the system can expel the air without pushing the coolant ahead of it.  Ultimately, you should reach 25-27 inches of vacuum when the system is free of air.

  9. 3 minutes ago, Vtx531 said:

    Thank you for your advice I really appreciate it. So you think there are two issues...


    1. Air in the system... say I use the vacuum fill method, do I need to completely drain the system first? I would imagine the answer is yes.


    2. Bleeder valve... I could actually see air bubbles coming out the bleeder valve between the top half and the bottom half where there screws are. What would be the fix for this?


    1.  The answer is no.  As long as the vacuum tool is above the liquid level, it will not pull coolant out.  I would suggest bringing the vacuum level up slowly as the system will "burp" which could splash coolant onto the vacuum unit.

    2. The bleeder has O-rings on it that can be replaced, and you can buy a complete new unit as well.  DO NOT use aftermarket pieces, they have proven to be of poor quality.

  10. 38 minutes ago, TipDown said:

    Ok, guess that's that then. Any idea roughly how much i'd get for my current used exhaust? It looks like it's in pretty good nick and installed within the last 2-4 years.


    In hindsight, should have thought about the practicality of this exhaust on the test drive. But it was sweet to my ears at 3500-6000rpm and I didn't have a chance to cruise at 70+ in 6th! Live and learn I guess 🙂


    With the top down its fine, maybe opening the windows slightly will help when i've got the top up.


    Really appreciate your responses.


    I'd check the markets in your area, what they sell for here is irrelevant.

  11. 4 hours ago, TipDown said:

    Yeah he didn't say it was a factory part (i asked if it was OEM, he said no) but said it was a Porsche exhaust. Just trying to find out what it is so I can call up and ask some garages what they can do with it. Is there any way to change the existing exhaust I have to a switch? I just don't want it loud all the time, especially as I want to drive it on the motorway sometimes - perhaps taking it abroad for some touring, and the drone reverberates around the cabin quite a lot with the hood up. Any slight touch on the accelerator has a really deep, loud sound which i'm guessing vibrates the soft top. Perhaps I can dampen it out in the cabin with something against the cloth?


    Any suggestions at all? I might have to look into just getting a new exhaust put in from Porsche with a button, but anything to avoid spending £1500 would be amazing.


    It would be a bit of a nightmare to convert a non switchable exhaust to a switchable version.  The factory has bypass pipes welded inside the muffler to facilitate the two pathways, the system you have does not, so they would have to cut it apart and weld them in.  I think that would end up costing you more than just buying the real thing and selling the unit you have.

  12. 11 minutes ago, Vtx531 said:

    Regarding the vacuum filler: I rented a pressure tester from autozone today. It has quick connect fitting that attaches to the expansion tank. I wonder if I could come up with a fitting from the hardware store that would attach. The U-view looks to be basically a ball valve with some fittings and a length of plastic hose?

    May try that later...


    In the meantime, last night I drove around. Car didn’t overheat but did have steam escaping the cap. The part number ends in -00 so I will order a new cap. I don’t think there should be steam escaping if the car is not overheated.


    Right now I am experimenting with the pressure tester. I pumped it up to 15 psi and as the pressure increase, the coolant level in the tank decreased. Is that normal?


    It started loosing pressure slowly but it looks like the pressure is escaping the bleeder valve. The metal pull tab isn’t doing anything because the pressure is causing the valve to pop up automatically. Is that normal?


    Seems to have leveled off at about 12 psi and not loosing pressure any further. When I let the pressure out, the coolant level comes back up and the bleed valve closes. Upon adding pressure again, the coolant goes down. Looks like the bleed valve starts to open at about 4 psi.


    You need an air compressor to operate the Uview and create vacuum.


    If you pressured the tank and the level dropped, you just proved you have air in the system.  Air is compressible, coolant is not, which is why the level changed.


    The system should hold pressure at 18 PSIG, if it drops lower, it is leaking.  Bleeder valves are known to do this.

  13. 9 minutes ago, Vtx531 said:

    Tried refilling again with the burp valve up (with distilled water for now). Still overheating after about 2 miles. The needle sorts of climbs slowly then gets jumpy and goes to the right.


    Looks like the tank could use more coolant. If I try to remove the cap, steam comes out and then the coolant level rises back up on its own and will overflow if I don’t replace the cap. So unable to put more coolant in.


    Now that the car has cooled down, I went out to Discover the tank was low and I could remove the cap and it stayed low. So I topped it off again.


    Do I need to just keep repeating this procedure of warming the car ip and letting it cool and refilling?


    The videos and writeups I have read about filling the coolant don’t really mention this problem. They make it seem like you can fill it up and drive normally (without overheating) and just keep topping it off over a few days.


    The recommended way of filling these cars with coolant is under vacuum, it is the way the dealer and any well equipped shop would do it specifically because of these issues.  I would suggest shortcutting all the top off and run it folderol and take it to someone with a Uview vacuum filling system; once connected, it will all be over in about 5 min.

  14. 12 minutes ago, Land Rover Range Rover said:

    Looking at the ECU I can not see ME 7.2 or any other version written. So far I found that there is a choice of two (ECU numbers) 99661860500 or 99661860400. Will try to call Porsche tomorrow to see if they can help me but somehow I doubt it. Wondering if someone has access to such a system and possibly could check for me 🙂


    According to Porsche's parts system, you should be a 996-618-605-00 (2001, 2.7L, manual trans). The ME7.2 is the firmware inside the box.

  15. 29 minutes ago, Land Rover Range Rover said:


    I just bought my first Porsche as always all my cars have to be non runners so I can learn more about them 🙂 Seems like the original issue was with the alarm control unit which was badly corroded inside so seller have changed ecu, key and alarm unit but car still would not start. On closer inspection I noticed marking on the ecu and alarm control units are for a Boxster S 3.2 (with white marker). As he attempted repair few years ago original ECU, Alarm ECU and KEY has been misplaced so I have no clue which "ECU kit" I should buy of my local breakers yard as there is a choice for 2.7. I noticed that there are at least 2-3 different part numbers for each unit and also anywhere I phoned they kept asking if my remote has 2 or 3 keys which again I am unsure what was the original one. Any help would be appreciated or maybe I can find somewhere online by the chassis numbers?


    Welcome to RennTech :welcomeani:

    The DME, immobilizer, and keys all have to match (come from a single vehicle), or be recoded by a dealer to match.  The DME version also has to match the original chassis as they changed with model years.  What year is the vehicle?

  16. 11 minutes ago, Nurbek I said:

    Had the same error code while going over mountain passes in Colorado. Anytime car had less than 3/4 fuel and 5K ft above sea level, it had really poor acceleration and bogging down. Had to keep it full to go anywhere on CO mountains. 


    Came back to east coast and even with less than 1/4 fuel no issue with accelerating around 400 ft above sea level. 


    I plan on picking up harbor freight fuel pressure tester kit. What else should I get to help with troubleshooting and going thru the checklist posted above? Durametric


    Be careful with the Harbor Freight fuel pressure tester, it is NOT designed for the pressures your DFI runs at, which can be as high as 3,000 PSIG

  17. 34 minutes ago, Vtx531 said:

    Thanks I already opened the vent valve and drove around and refilled with coolant multiple times but that didnt seem to help.


    Is that large hose coming out of the thermostat supposed to feel full of coolant and hot when the car is warmed up? Could there be a blockage?


    I dont really understand and couldnt find a diagram of the plumbing for the cooling system so I don’t know what hoses are what.


    i am thinking I need to take off all the plastic underbody panels and check fo blockages but hard to imagine that both radiators would be blocked, there should still be some flow I would think.


    This should help, it shows how the coolant flows in your car (red is hot out, blue cool returning):



  18. 9 hours ago, Vtx531 said:

    It has already had the waterpump, thermostat, and coolant temp sensor replaced by local shop (prior to me buying it).


    It seems like the large hose coming out of the thermostat is not getting hot and not filling with coolant (when the car is warmed up). I put my hand on the hose and it is hot near the thermostat but not further down the hose. Almost feels like it is full of air, I can squeeze it and there is pressure inside but doesn’t feel the same as the other large coolant hose.


    I tested the thermostat in boiling pot of water and verified it is opening.


    I can hear the fans running. Fan fuses are good.


    What should I check for next?




    Sounds like trapped air.  Fastest way to correct this is to pull a vacuum above the coolant in the surge tank and get the air out, or open the coolant vent valve and "burp" the system.

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.