1990 Chevy Lumina Fuel pressure test results

1990 CHEVROLET LUMINA
85,000 MILES • 6 CYL • FWD • AUTOMATIC
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AJMEYERS
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I have tested the fuel system and found that the fuel pressure would drop to 0 as soon as the fuel pump stopped. How can I tell if if is due to a leaky injector or the fuel pump assy?
Jan 28, 2009 at 4:04 PM
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RASMATAZ
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When the pump is turned off or stops running, the system should hold residual pressure for several minutes (look up the specs to see how much pressure drop is allowed over a given period of time). If pressure drops quickly, the vehicle may have a leaky fuel line, a leaky fuel pump check valve, a leaky fuel pressure regulator or one or more leaky fuel injectors. Low residual fuel pressure can cause hard starting and vapor lock during hot weather

You have to open it up
Jan 28, 2009 at 4:14 PM