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Old 10-22-2023, 04:34 PM
86911TLCAB 86911TLCAB is offline
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Default 3.2 swap into a 82 SC

My SC has a 3.2 swap done a few years ago. The electrical connections all made by another friend and I am having some occasional starting issues. As I have been researching, I have come to understand the fuel pump relay in the luggage compartment doesn’t play the same role as it did before with a 3.0 engine. I have found documentation for the wiring set up and now know how the DME and the DME relay are all connected. My question: what role does the fuel pump relay in the luggage compartment play. I know it is something as if I pull it when the car is running, it will stop. So obviously it is still part of the path to get power to the fuel pump, but am struggling to understand what it is. Would appreciate any info from Anyone who may have done this swap or just understands how the DME would allow the voltage to get to the pump to start. Thanks in advance.
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Old 10-22-2023, 07:24 PM
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Can you also give more of an explanation as to how the car tries and fails to start? Are you getting spark? does the cylinder smell like fuel?

I have 5 years of starting only 50% of the time on my 3.2, but once it was running it was great, and it either didn't catch at all, or it started in 1/2 a second. It turned out to be the flywheel sensors (which after 5 years of problems, Matt De Maria figured out in a few minutes!).

BTW, your engine was supposed to be MY engine, correct?
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Old 10-23-2023, 07:11 PM
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Hello Pete…Smile…the few times it didn’t start, it would turn over but not kick on…no fuel smell. This past time I took things apart…did continuity tests…tested the Dme relay and all power and disconnected the dme wiring, put it all back together and everything working for now. Intermittent problems are hard to find, so will keep a watch. But my question is more related to the fuel pump relay in the luggage compartment. How or is voltage getting to the fuel pump via the relay…with the ign in the on position I have no voltage at any of the points on the socket. Just a gap in my understanding that I want to fill.
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Old 10-23-2023, 10:58 PM
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Just to complete my comment, it was the flywheel sensor GAP that was wrong - 2.4 mm instead of 0.8 mm. They aren't powered, and the voltage from the flywheel drops off by the square of the distance. They can be adjusted and replaced with the engine in the car - just remove the real left-side wheel to get to them. I replaced them (different car) one evening at VIR with just an Allen wrench and a screwdriver (and a jack and an impact wrench).
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Old 10-24-2023, 05:51 PM
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Thanks…will take a look at it…and have replaced them before.
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Old 10-25-2023, 08:43 PM
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Quote:
Originally Posted by 86911TLCAB View Post
But my question is more related to the fuel pump relay in the luggage compartment. How or is voltage getting to the fuel pump via the relay…with the ign in the on position I have no voltage at any of the points on the socket. Just a gap in my understanding that I want to fill.
You should not need the fuel pump relay at the fuse box for the 3.2. That's what the DME relay is for. You could run a wire from the DME Relay 87B to the pump, but better use the fuel pump fuse from the fuse box, and bi-pass the SC relay. The fuse should be a 25amp fuse. See below, RED/Green wire.
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  #7  
Old 10-26-2023, 04:21 PM
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Thanks...I will explain how my SC has the 3.2 wired in so I can help you help me understand how this works....back with more soon!
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