iHateVolvoPeople
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- Joined
- Feb 1, 2014
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- Midwest
SOLVED: a bad 556 ecu was not turning on the pumps and possibly not allowing the radio suppression relay to function either. Symptoms were a crank no start when very cold out. I would notice that the pumps were not priming and it would obviously not start. Swapped in an ECU from my 93 245 and the pumps primed. Car fired right up.
1990 740 na lh2.4.
Car is great when it runs but sometimes on really cold starts (15F today) it’s a crank and no start. I do not hear the fuel pump relay kick on. I removed the fuel pump relay in jumpered it to where both of the fuel pumps work but I was still getting a no start. I am assuming it’s getting fuel at the rail considering almost the entire fuel system is new. Is a bad radio suppression relay a possible cause of a crank no start? Even if the engine is getting fuel maybe the injectors or not firing. I’ve tried to fuel pump relay is but neither seem to be reliably priming and key position to on a regular basis. After everything is warmed up I hear it prime and it starts like normal.
1990 740 na lh2.4.
Car is great when it runs but sometimes on really cold starts (15F today) it’s a crank and no start. I do not hear the fuel pump relay kick on. I removed the fuel pump relay in jumpered it to where both of the fuel pumps work but I was still getting a no start. I am assuming it’s getting fuel at the rail considering almost the entire fuel system is new. Is a bad radio suppression relay a possible cause of a crank no start? Even if the engine is getting fuel maybe the injectors or not firing. I’ve tried to fuel pump relay is but neither seem to be reliably priming and key position to on a regular basis. After everything is warmed up I hear it prime and it starts like normal.
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