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Normal fuel pump operation?

Old Aug 18, 2007 | 01:21 PM
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Normal fuel pump operation?

89 GTA 305 LB9

The car will typically start when cold, after sitting overnight. But when hot, have no start problems.

Sometimes - key on, pump runs 2 sec. and builds 40-43 psi on the gauge, and holds. No start.

Sometimes - key on, pump runs 2 sec. and builds no pressure. No start.

Sometimes - key on, pump runs 2 sec. and builds 40-43 psi on the gauge, and drops off immediately to zero. No start.

When cranking always 40-43 psi.

Dump a few ounces of gas in the plenum, and it will run.

New TPS and new ECM. No better.

Time for a new pump?
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Old Aug 18, 2007 | 02:06 PM
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From: Sheboygan Wisconsin
Car: 91`camaro RS
Engine: 5.7l vortec T.B.I.
Transmission: STS 700r4
Axle/Gears: 9bolt-3.27
Re: Normal fuel pump operation?

sounds like a bad regulator or faulty injectors and or inj. wiring
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Old Aug 18, 2007 | 04:13 PM
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Re: Normal fuel pump operation?

After further review:

System will prime everytime given 10 seconds between tries. But the pressure does not hold. Pinched the pressure side of the line after prime and the pressure holds. Repair manual says bad pump.

The car will start if you do not delay the time between key on and start.
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Old Aug 20, 2007 | 07:03 AM
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Re: Normal fuel pump operation?

Installed new pump, problem solved.
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