Distributors and Trigger Points (New Dizzy Installed), Troubleshooting Parts - CHT appears bad |
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Distributors and Trigger Points (New Dizzy Installed), Troubleshooting Parts - CHT appears bad |
tvdinnerbythepool |
Sep 9 2021, 08:43 AM
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#1
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Member Group: Members Posts: 310 Joined: 24-July 18 From: Olympia, WA Member No.: 22,336 Region Association: Pacific Northwest |
Hey all,
I am still chasing down an intermittent RICH condition when the car is fully warmed up. 1.7L D-Jet After fully warmed up with a tuned and rebuilt MPS I can come to a stop light and idle steady at 850rpms, next stop light it's bogging down to almost 200-300 and barely running. Then next light it's idling normally again. Some days I have no issues with idle at all, others I do. I've gone through all the components and troubleshot my way through everything on the PBANDERS list of "my car is running rich". I am as confident as I can be through extensive troubleshooting and testing that my ECU, AAR, MPS, CSV, Vacuum Leaks, CHT, Injectors, Fuel Pressure etc are all good. All new wiring harnesses, plugs, plug wires, cap, rotor, coil, etc. The ONLY thing I haven't worked on is the distributor. I am reading up on the possibility of the Trigger Sensor Contacts being warn and bouncing possibly shooting off extra injection pulses...could this be the cause of the intermittent problem? It doesn't have points anymore, but a petronix I believe. What do you guys think? Is there an easy test for this or do I replace the trigger contacts or the whole dizzy? Cheers! (IMG:style_emoticons/default/beerchug.gif) |
tvdinnerbythepool |
Sep 30 2021, 03:00 PM
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#2
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Member Group: Members Posts: 310 Joined: 24-July 18 From: Olympia, WA Member No.: 22,336 Region Association: Pacific Northwest |
Update below
CHT: measured 49.7K Ohms at 63 degrees (OUT OF SPEC - NEW ONE IN THE MAIL) MPS: -Vacuum holds all day long at 15" -Calibrated with Wavetech to PBanders specs, very close specs to another sealed unit I have to compare to. TPS: Tested perfectly, Mild wear on the Board but not needing replacement. Cleaned and re-calibrated. Compression test: These are cold numbers, will repeat when new CHT installed with some hot numbers. #1: 145psi #2: 150psi #3: 155psi #4: 155psi Pleasantly surprised by those numbers, all within 10psi so whatever wear exists is nice and even. Will install new CHT hopefully tomorrow night if it gets here in time. Still need to check the intake plenum and possibly bypass the CSV. I am not convinced it's a vacuum issue as I have very low idle issues, not high, but will inspect. Really looking like the CHT is the culprit or the ECU. And now I have the infamous modified 13mm deep socket, Lol |
DRPHIL914 |
Oct 1 2021, 11:10 AM
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#3
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Dr. Phil Group: Members Posts: 5,767 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
Update below CHT: measured 49.7K Ohms at 63 degrees (OUT OF SPEC - NEW ONE IN THE MAIL) MPS: -Vacuum holds all day long at 15" -Calibrated with Wavetech to PBanders specs, very close specs to another sealed unit I have to compare to. TPS: Tested perfectly, Mild wear on the Board but not needing replacement. Cleaned and re-calibrated. Compression test: These are cold numbers, will repeat when new CHT installed with some hot numbers. #1: 145psi #2: 150psi #3: 155psi #4: 155psi Pleasantly surprised by those numbers, all within 10psi so whatever wear exists is nice and even. Will install new CHT hopefully tomorrow night if it gets here in time. Still need to check the intake plenum and possibly bypass the CSV. I am not convinced it's a vacuum issue as I have very low idle issues, not high, but will inspect. Really looking like the CHT is the culprit or the ECU. And now I have the infamous modified 13mm deep socket, Lol i have the d-jet as well but '75 so they are set up just a bit different, sounds like once you hvae a good CHT( i have 3 on hand just in case) you will get it going, but, did you try to get new set of trigger points plate for the FI triggers? they are out there, i have several but will not part with them as i keep them for my OEM distributor for back up in case of 123 failure and for originality etc . Anyway i have run the 123 for 3 years and it is doing fine, i dont have vac advance so running Curve D for no vac advance for a '75. set your timing, follow instructions, verify proper function of CHT and MPS before you throw the 123 aside., Keep your OEM one, get a set of fi tp plate contacts and get Norburt's calibration tool for the FI triggers. |
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