 Ignition Question, My diaphragm was cracked--still not Prego! |
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| Robarabian |
 Sep 11 2022, 05:41 PM
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914 A Roo  Group: Members Posts: 695 Joined: 11-February 19 From: Simi Valley, Kalifornia Member No.: 22,865 Region Association: Southern California 
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Collective brain trust help needed.
Car is a 1971 1.7. Finished my rebuild, now 1911 CC's. (ECU non adjustable) Car runs a Pertronix Ignition. Distributor was disassembled, cleaned and re-lubed. Static timed the car and started it, and ran it for about 18 minutes at 2500-3000 rpm to break in the cam and rings. Did my oil change and then it sat for a few weeks. Started it to finally set the timing and it started running rough, and I can tell it is on 3 cyl, sometimes 4, and spits, coughs etc. I know it isn't timed right and cant time it until it is on 4 cylinders. Fuel pressure on an inline gauge is at 30 psi. Pulled #1 and #2 plugs, they are the right color. Pulled #3 and #4 and they are wet, and have remnants of being the right color from the cam break in. Checked all the connections, but don't quite know where to start. The trigger points were clean in the distributor when I disassembled it, and it ran right for cam break in. Cap, rotor, plugs, wires are all new. MPS holds vacuum. Thoughts on what I am missing here or where would you start digging first. I thank you in advance. |
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| Robarabian |
Sep 15 2022, 08:05 PM
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914 A Roo Group: Members Posts: 695 Joined: 11-February 19 From: Simi Valley, Kalifornia Member No.: 22,865 Region Association: Southern California
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Good news. I ordered Tangerine's MPS rebuild kit. While waiting for its arrival, I tested mine for Vacuum. Zilch.
Took it apart (it appears to have been rebuilt before) and take a look at the diaphragm. A total loss. So Thank you for pointing me in this direction, I think this will be a HUGE step to getting it running. I also appear to have had the wrong Head temp sensor, so I sourced what I believe is the proper one and will install this weekend, hopefully in conjunction with a rebuilt MPS. Ill keep you posted.  |
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Posts in this topic
Robarabian Ignition Question Sep 11 2022, 05:41 PM
bkrantz Can you check for spark at #3 and 4? Sep 11 2022, 08:34 PM
Robarabian It is on the list for sure. I will disable the fue... Sep 11 2022, 09:05 PM JeffBowlsby All three FI grounds making good contact? Sep 11 2022, 08:59 PM Robarabian YEs, I checked the 3 prong connector and everythin... Sep 11 2022, 09:04 PM Robarabian Ok, some progress.
It runs on 4. I brain farted ... Sep 12 2022, 08:03 PM emerygt350 I would suspect a lean condition at cold start. I... Sep 13 2022, 04:50 AM Robarabian I have a spare AAR somewhere, I will clean and tes... Sep 13 2022, 08:23 AM mgphoto
I have a spare AAR somewhere, I will clean and te... Sep 13 2022, 09:08 AM emerygt350
[quote name='Robarabian' post='3029253' date='Sep... Sep 13 2022, 10:28 AM Robarabian I will recheck the injector part numbers, I did re... Sep 13 2022, 10:44 AM mgphoto Your injectors may be to large, you are probably t... Sep 13 2022, 03:36 PM JeffBowlsby In your first post you said your “MPS holds vacu... Sep 15 2022, 08:46 PM Robarabian Yeah, I didn't give it long enough when I test... Sep 15 2022, 09:36 PM emerygt350 Good find. Make sure you follow Chris's instr... Sep 16 2022, 04:40 AM Robarabian Thank you I intend to. I did order the tool kit as... Sep 16 2022, 08:10 AM emerygt350
Thank you I intend to. I did order the tool kit a... Sep 16 2022, 11:01 AM |
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