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Discussion Starter · #1 ·
when you first turn your ignition to the on position but havent cranked it yet are you supposed to hear a humming sound for a few seconds by the fuel pump?

also how can you tell if your main relay is bad?

Robert
 

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25psi Bliss
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The stock ECU has a fuel pump safety feature: If the engine is not cranking, nor running, the FP will not operate. The pump is not operable till the key is in the START position, and the CIRCUIT OPENING RELAY activates the IGN circuitry.

HTH
 

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Discussion Starter · #4 ·
the problem is that I was NOT hearing the fuel pump come on when I turn the key to the on position b4 actually attempting to start it.....where is the circuit ignition relay? The whole situation is strange...I've been trying to clear a code 52 so I rewired the knock sensors straight to ECU & didnt clear the code but was still running so then I was swapping in a brand new Knock Sensor and car was cranking faster than it normally does but wouldnt start. Couldnt figure out what happened but after f'ing with it till 5am out of nowhere it started up just fine....alas still a code 52
 
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