Long time to start cold

Hi I have a 1988 chevy celebrtity 2.8 v6 Great car for many years. But now engine cranks over for about 5 seconds or so before it fires up. (almost always when it sits overnite)
I used to hear the fuel system pressurize when I would turn the ignition key to the on position (but not crank it over) Now I do not hear the Humming sound of the fuel system pressurizing prior to starting.
Once the engine starts, the car runs fine at idle or even at high speeds.
What part could have failed ? Thanks for any help Xray
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Check the fuel pump relay. If it fails, the fuel pump will only come on after the oil pressure switch closes, which will take some cranking time to happen..
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Robert Hancock Saskatoon, SK, Canada
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I replaced the fuel pump relay today Still acts the same. Another other ideas or suggestions would be appreciated. Xray

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If the fuel pump relay is OK, and the fuel pump still doesn't run when the key is turned to On, either the ECM is bad, or there is some kind of wiring problem. Probably you need to get yourself a wiring diagram and a voltmeter, and figure out if power is getting to the relay coil when it should, and if not, trace it back and figure out why..
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Robert Hancock Saskatoon, SK, Canada
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Hi There,
IMHO, Robert's idea was a good one. Seeing that didn't do it for you, try hooking a fuel pressure gauge to the rail. 40+ PSI is the norm on these cars. Pressure should hold with key off. Let us know what the gauge tells you.
Regards, Al.

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Fuel pressure regulator???????

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