Running on cylinders 1 & 3 only... |
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Running on cylinders 1 & 3 only... |
AnthraxBird |
Sep 20 2016, 09:29 AM
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#1
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Newbie Group: Members Posts: 5 Joined: 20-September 16 From: Indiana Member No.: 20,417 Region Association: None |
Hey guys, new here. My buddy and I are working on a 72 1.7L and it's only running on 1 and 3. Cleaned and checked the trigger points, still no dice. Now, when you unplug the connector for the trigger points, it runs on all 4, for about 3 seconds til it starves of fuel. Input?
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pbanders |
Sep 20 2016, 10:10 AM
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#2
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Senior Member Group: Members Posts: 939 Joined: 11-June 03 From: Phoenix, AZ Member No.: 805 |
Hey guys, new here. My buddy and I are working on a 72 1.7L and it's only running on 1 and 3. Cleaned and checked the trigger points, still no dice. Now, when you unplug the connector for the trigger points, it runs on all 4, for about 3 seconds til it starves of fuel. Input? Look at my web page for suggestions. I recommend you test every component in the FI system for basic operation, my page has info on how to do this. For your specific problem, test the trigger points, the wiring harness (both the TC's, grounds, and the injector leads). If you have spares (which everyone who has a nearly 50-year-old car should have (IMG:style_emoticons/default/smile.gif) ), swap in known good/new TC points and ECU. You might also want to consider buying a noid light for Bosch injection, it visually shows whether an injector is firing or not. https://www.amazon.com/OTC-7188-Bosch-Noid-...e/dp/B000P72CMW |
AnthraxBird |
Sep 20 2016, 11:00 AM
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#3
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Newbie Group: Members Posts: 5 Joined: 20-September 16 From: Indiana Member No.: 20,417 Region Association: None |
Ok I'll look at it. Funny you said that, we have a no voltage issue on the fuel pump, but I suspect it's the relays as they're corroded as hell and falling apart.
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pbanders |
Sep 20 2016, 03:03 PM
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#4
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Senior Member Group: Members Posts: 939 Joined: 11-June 03 From: Phoenix, AZ Member No.: 805 |
Ok I'll look at it. Funny you said that, we have a no voltage issue on the fuel pump, but I suspect it's the relays as they're corroded as hell and falling apart. Just checking, I assume you know that the fuel pump is only energized by the ECU for 1.5 sec when you turn the key to the "on" position, right? When you turn the key to "cranking/start", then the fuel pump will turn on while cranking. If the engine doesn't start, and the key returns to "on", the fuel pump will turn off. The only way the fuel pump will stay running in the "on" position of the key is if the engine is running, too. |
AnthraxBird |
Sep 21 2016, 07:37 AM
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#5
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Newbie Group: Members Posts: 5 Joined: 20-September 16 From: Indiana Member No.: 20,417 Region Association: None |
Ok I'll look at it. Funny you said that, we have a no voltage issue on the fuel pump, but I suspect it's the relays as they're corroded as hell and falling apart. Just checking, I assume you know that the fuel pump is only energized by the ECU for 1.5 sec when you turn the key to the "on" position, right? When you turn the key to "cranking/start", then the fuel pump will turn on while cranking. If the engine doesn't start, and the key returns to "on", the fuel pump will turn off. The only way the fuel pump will stay running in the "on" position of the key is if the engine is running, too. Yessir. No power at all on the pump. |
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