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Re: Fuel Pump Always Running Posted by Gary Stottler [Email] (#1463) [Profile/Gallery] (more from Gary Stottler) on Sun, 27 Oct 2019 09:03:18 In Reply to: Fuel Pump Always Running, Paul D, Thu, 24 Oct 2019 12:09:57 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Paul,
The ignition switch should turn on the main relay when "on" and the fuel pump relay when cranking or running. I suspect that someone has bypassed or jumpered the fuel pump relay. On early CIS cars ('75 for sure, maybe '76-77) the system "sensed" a running engine with a set of contacts in the airflow plate that were closed only when the plate raised, indicating airflow). That was problematic on several levels and was later replaced with a relay which checked for ignition pulses (which caused it's own problems). Anyway, if someone was having trouble with that they might have jumpered the fuel pump relay in such a way that it runs all the time (bad idea on many levels). Do you have the wiring diagram? If not let me know and I can scan it and send it to you.
Best,
Gary
_______________________________________ Gary Stottler
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