long cranking start ?

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bpman1234

Well-Known Member
Joined
Jan 24, 2011
Messages
2,001
ook the car is running great .but it takes about 4 second to start is there anything i can do to fix it in the gen2 or what to check ?thanks as always in advance.
 
Sounds like its running on the oil switch. Do you hear the fuel pump prime when you turn the key to on position?

1 of 2 things. The fuel pump relay is bad or the fuel pump signal in the ecm went south.
 
no I don't hear the prime going on when I hit the switch. could that be because I don't have my oil pressure switch plug hooked up cause I have the aftermarket vdo oil pressure gauge

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Last edited:
ok gonna put a tee where the oil pressure switch goes and plug the stock oil pressure switch and plug back in and see what happens.oh and i double checked to see if it was priming and it is .
 
The oil pressure switch is a secondary contact for the fuel pump. If the fp relay or signal fails, the oil switch will take over. In a car that has lost the signal or has a bad relay, it will crank longer before it starts due to needing a few cranks of the starter to build enough oil pressure to close the contact in the switch thus resulting in longer crank times.

Rick
 
Your relay has to be fine since it does crank eventually. Since you disconnected your backup system, you have to be running on the normal fuel circuit.

When you turn the key on you should hear the fuel pump run for about 2 seconds.
 
okay so all I have to do is put back to stockswitch with the stock plug with a tee? like I said above and I should be okay then right

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that will return your back up to working order. It won't address your long cranking issue.
 
First thing I would check at this point is the fuel pressure after you turn off the vehicles engine. The fuel pressure should hold for a little while, if the fuel pressure is dropping fast after the fuel pump shuts down, then the check valve in the fuel pump could be leaking and after the vehicle sits the fuel line could be empty and it would take a few seconds to fill the fuel line back up and have fuel at the fuel rail. Earl is correct in stating that the fuel relay and PCM signal to energize the relay are good, since you do not have the oil switch backup circuit anymore.
when the fuel pump check valve leaks, it is a leak back into the fuel tank, not an external leak that you would smell or see on the floor. Just wanted to make sure there is no confusion.
 
Last time i check the gauge i didnt have a fast leak down the pressure held for a while.but i will check it again .i have a hood mount but dont leave it out all the time .i leave it in the engine bay when not tunning or trouble shooting.whay if all checks good there.then where should i go.?

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There are allot of turbo Buicks that don't hold fuel pressure and they do not take 4 seconds to start.

Does it act the same way when the engine is warm and cold? Same long cranking times?

Rick
 
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