1990 Pontiac Grand Prix Engine cranks over easily but won`t

1GRD57

MEMBER
1990 PONTIAC GRAND PRIX
6 CYL
FWD
AUTOMATIC
160,000 MILES

Help. My car won`t start. It cranks over easily but won`t start. When I spray some instant start in the intake manifold it will sometimes start. I can hear the fuel pump hum when I turn the key on. Apparently the pump was changed over a year ago by the previous owner. Thank you

Saturday, August 9th, 2008 AT 1:45 AM

3 Replies

MHPAUTOS

MECHANIC
31,937 POSTS

Hi there,

Start with changing the fuel filter and have the fuel pressure at the injector rail checked, also check for injector pulse, but if it wants to start with starting fluid I wold be checking fuel supply first, start here.

Mark (mhpautos)

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Saturday, August 9th, 2008 AT 3:27 AM

1GRD57

MEMBER
2 POSTS

Fuel filter is replaced, injector tube has fuel pressure and injectors pulse is good. So I am still at a loss thanks again G

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Saturday, August 9th, 2008 AT 11:03 AM

MHPAUTOS

MECHANIC
31,937 POSTS

Hi there,

See if you can get an ignition test done on an oscilloscope, as this will give you all the ignition voltages, you may have low ignition voltage through a faulty coil. And the higher flash point of the starter fluid is the reason it will start on it, look into this next.

Mark (mhpautos)

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Saturday, August 9th, 2008 AT 6:49 PM