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Crank Issue

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Old Jan 29, 2012 | 12:36 PM
  #1  
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kdtomczak
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From: Columbia SC
Default Crank Issue

In the mornings or after a long period of non usage, my '86 will take a couple long tries to crank? Is my starter going bad?
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Old Jan 29, 2012 | 01:09 PM
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When I hear "cranking" I think of the starter actually spinning. If that's the case, and the engine is not firing, then I would assume that the starter is OK and your problem is elsewhere. If, however, you mean that your starter is not functioning, then that isolates the problem to somewhere within the starting circuit. Can you clarify?
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Old Jan 30, 2012 | 04:16 PM
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yeah the engine turns but I'll turn the key for about 5 seconds...and the engine won't fully start. I'll repeat that process about 3 times before it finally fully starts. After that it usually starts fairly easily.
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Old Jan 30, 2012 | 05:25 PM
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If the engine is cranking (turning) through the entire time you're pushing the key, then it's going to be a fuel problem. Put a fuel pressure regulator on it and you should get 35 pounds within a couple of seconds. Often, the fuel pressure regulator will go bad (it's right underneath the intake plenum on the passenger side), allowing the fuel to drain back towards the tank. So when you start it, it takes a five or ten seconds for the fuel system to fully pressurize from the tank.

Also, there's a cold start injector on the driver's side that injects a shot of fuel into the intake when it's cold, but first, check the fuel pressure.
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Old Jan 30, 2012 | 05:36 PM
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In all likelihood, your fuel pump relay is bad. GM engineers provided a second path to energize the fuel pump in the event of relay failure.....the oil pressure switch. Once oil pressure hits about 4 psi, the switch closes, and the fuel pump is energized.

Do you hear a 2 second fuel pump prime when you turn the key on? If not, replace your fuel pump relay and it will start much faster.
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Old Jan 31, 2012 | 12:20 AM
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Turn off the radio and A/C and listen for the fuel pump at key on. It should run for 2 seconds. It might help to have somebody else turn on the key and for you to listen at the tank for the pump sound.

Pull off the vacuum line on the fuel pressure regulator to see if there's fuel in it.

Report back to us with the results of the above two tests and we can go on from there.

The best troubleshooting tool for fuel problems is a fuel pressure gauge. About $40-$50. An excellent investment if you want to work on your car.
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Old Jan 31, 2012 | 08:38 AM
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Originally Posted by Cliff Harris
Turn off the radio and A/C and listen for the fuel pump at key on. It should run for 2 seconds. It might help to have somebody else turn on the key and for you to listen at the tank for the pump sound.

Pull off the vacuum line on the fuel pressure regulator to see if there's fuel in it.

Report back to us with the results of the above two tests and we can go on from there.

The best troubleshooting tool for fuel problems is a fuel pressure gauge. About $40-$50. An excellent investment if you want to work on your car.
Harbor Freight has them on sale for $20 every so often. Test your fuel pressure at initial key on and see what you have.
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Old Jan 31, 2012 | 08:53 PM
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Don't confuse the sound of the abs doing it's test with the sound of the fuel pump. Took me a while to learn that.
There are two pins you can jump on the obd connector to enable the pump relay, but I dont remember which.
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Old Jan 31, 2012 | 09:34 PM
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Originally Posted by F22
there's a cold start injector on the driver's side that injects a shot of fuel into the intake when it's cold, but first, check the fuel pressure.

CSI works like a choke on carb car; gives a extra fuel hit on a cold crank
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