"Motorpsycho Jim" wrote in message news: snipped-for-privacy@storefull-3313.bay.webtv.net...
Two items plus the computer control the fuel pump. One is the fuel pump relay, the second is one of the two oil pressure sending units. The computer fires the relay which fires the pump when you turn the key on for a second or two to pressurize the system untill the engine starts. The back up is the oil pressure sending unit which will allow the pump to come on when oil pressure builds. The sending units primary job is to shut the pump off in case of an accident. Its secondary job is to keep the fuel pump running once the engine is running. A nice side affect is it will shut the fuel pump off if you loose oil pressure. The Chevrolet Vega was the first GM to use this set up. Given it doesn't start even after a long crank, that leaves the computer and the fuel pump itself, unless it has been hard starting for a while. This second oil pressure switch is an SPST NC/NC switch with an over lap between the two positions (NC=normally closed) One NC side feeds the red check engine light, the other side feeds the fuel pump. If you can get to the wiring harness you can check for voltage when some one cycles the ignition switch, if it has voltage, its the pump, if it doesn't then I would be looking at the ECM, and the harness itself.. All of this assumes you have found some way to check for fuel pressure besides looking at the injectors to see if they are delivering fuel. If the injectors aren't opening, all the fuel pressure in the world wont do no good. And I am sure a few others here will have ideas as well Whitelightning
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Is the fuse blown?
Check fuel pump ground, grounds get nasty when temps drop
j.w. cols. ohio
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