Have replaced fuel pump and ECM but fuel pump at start is questionable if it will turn on or not. What else can I check? If it starts, it will stay running, just if that fuel pump will turn on when you turn the key is the question, don't know what else to check?
2003 Sunfire fuel pump issue
- Thread starter jimp7711
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a bad contact in the ignition switch that periodically causes the pump relay not to engage. Arent you using a voltmeter to determine where the issue is?
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At relay, test light shows terminal closest to firewall and inboard engine terminal of relay gets power when key is turned. If standing facing engine, right inboard post gets power, nothing on other 3 posts. Back at the plug underneath for fuel pump, have two hot posts in seven plug box at fuel pump plug when key is turned to on. I am at a loss for clues. Would the ignition switch still be an issue knowing this?
no difference. The relay clicks when key is turned.
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this link has a fuel pump circuit diagram which may help you to determine if power is going to the pump from the relay
http://www.justanswer.com/pontiac/2rxv3-pontiac-sunfire-2004-2-2-liter.html
http://www.justanswer.com/pontiac/2rxv3-pontiac-sunfire-2004-2-2-liter.html
with the test light tracked power all the way to the pigtail plug for the fuel pump right up to the fuel pump. It would not pass through the connector on the fuel pump to the inside of the fuel pump. Luckily I bought pump from Amazon last Oct. Amazon is sending free replacement w/1 day ship will be here Sat.
Thanks for your input. Hopefully this will be the last time I drop that fuel tank!
Thanks for your input. Hopefully this will be the last time I drop that fuel tank!
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how can you say you have power at the pump then? does the voltmeter show power when you turn the key to run? have you checked the ground? if you have power to the pump run a temporary ground wire to check the harness ground
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I was wrong, fuel pump sending wire had power, nothing to the plug for power to pump. Does anyone know where that power wire runs back to? Shows power to pump relay so somewhere between these two points. Need to know where the power grey wire to pump runs back to.
traced all the way to one of the 4 ports on relay, can send power all the way back to the pump from there and it works! Now what makes the relay push power through it? Could it be the ignition switch?
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well thought it was fixed, after WalMart trip came out to start and no pump noise. Pulled relay and reset still nothing. Had wire from working on so jumped positive battery to post under relay to send power to pump, that got me home. Removed wire once home kept running. Restaarted just fine. Issue seems to be between relay and battery has a sort. Does anyone know if that power between those points runs through ignition switch?
Found short beside drivers side door step trim panel in grey wire. Ended up replacing grey wire from relay box all the way back to just before exit to plug for fuel pump under back. So far, been reliable. Starts every time. Grey wire goes from reply under hood all the way to pump. If you have power at reply but not at pump, I would recommend replacing wire. What a nightmare to track it down!