96 LT1 Hard Start
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Joined: May 2003
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From: Virginia Beach VA
96 LT1 Hard Start
I first noticed the problem a few days ago after the car had sat for about 3-4 days. I was able to get it started after pumping the gas pedal (lightly) a few times. Pulled it out into the drive-way and shut it off. When I tried to re-start, it did start, but I heard what sounded like a 'clunk' or 'belt' sound from up front.
After it starts, the car runs fine and does start after a short shut down.
I heard it could be several things, but I thought I would ask you all your thoughts.
The car has about 50,000. As far as I know it has the original Opti-spark.
After it starts, the car runs fine and does start after a short shut down.
I heard it could be several things, but I thought I would ask you all your thoughts.
The car has about 50,000. As far as I know it has the original Opti-spark.
Race Director
Joined: Dec 2006
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Suspect fuel pressure isn't right. Test with a FP gauge at idle, rev to 2k, shut down, and 30 mins after shut down. You can tape a FP gauge to the outside of the windshield so that you can see it from the driver's seat while you're sorting it out.
If Fuel pressure is low and you don't have a stream of gas pouring out of the car then your suspects are fuel pressure regulator, fuel pump check valve, leaking injector(s), fuel pump.
You will also want to listen as you turn the key from off to run (not start!) and listen for the fuel pump to run for a couple of seconds. If you don't hear it check the fuel pump relay.
Pumping the gas pedal should have no effect like it used to have on carb's cars BTW.
If Fuel pressure is low and you don't have a stream of gas pouring out of the car then your suspects are fuel pressure regulator, fuel pump check valve, leaking injector(s), fuel pump.
You will also want to listen as you turn the key from off to run (not start!) and listen for the fuel pump to run for a couple of seconds. If you don't hear it check the fuel pump relay.
Pumping the gas pedal should have no effect like it used to have on carb's cars BTW.
Last edited by 94z07fx3; Nov 24, 2012 at 10:40 AM.
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Joined: May 2003
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From: Virginia Beach VA
thanks
I'll have to get outside help as far as the pressure gauge goes.
After sitting for about 7 hours, I tried to start it. I first just turned the key to 'on' and listened for the relay. Did this for about 2-3 seconds. Had the hood up and the radio off. Not sure what the relay sounds like, but the engine started right up.
I'll have to get outside help as far as the pressure gauge goes.
After sitting for about 7 hours, I tried to start it. I first just turned the key to 'on' and listened for the relay. Did this for about 2-3 seconds. Had the hood up and the radio off. Not sure what the relay sounds like, but the engine started right up.
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Joined: Oct 2005
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From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
There isn't an accelerator pump like on the old carbureted engines.
So, pumping the gas pedal won't make any difference.
But holding the pedal all the way to the floor has been mentioned as a way of clearing a flooded condition.
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Joined: May 2003
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From: Virginia Beach VA
Curious to know what "pumping the gas pedal" would do on a fuel injected car?
There isn't an accelerator pump like on the old carbureted engines.
So, pumping the gas pedal won't make any difference.
But holding the pedal all the way to the floor has been mentioned as a way of clearing a flooded condition.
There isn't an accelerator pump like on the old carbureted engines.
So, pumping the gas pedal won't make any difference.
But holding the pedal all the way to the floor has been mentioned as a way of clearing a flooded condition.
You're right about holding it down...
From the owners manaul.."If it doesn’t start within 10 seconds, push the
accelerator pedal all the way to the floor, while you
hold the ignition key in START. When the engine
starts, let go of the key and let up on the accelerator
pedal. Wait about 15 seconds between each try to
help avoid draining your battery."
Le Mans Master
Joined: Jan 2006
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From: Orlando FL
At this point I would just have a look at the FPR (fuel pressure regulator) vacuum line to see if there is any fuel in it. If it is draining back into your manifold, it would be to rich and make starting hard.
Pull off the vacuum line and see if it is wet. Pressurize system (key on 5 seconds) and see if it leaks out of FPR vacuum connection.
I think mine leaked down in about 15 minutes. Depending how fast the leak is will make starting hard at different lengths of time from shutdown. Happened twice to me now.
Pull off the vacuum line and see if it is wet. Pressurize system (key on 5 seconds) and see if it leaks out of FPR vacuum connection.
I think mine leaked down in about 15 minutes. Depending how fast the leak is will make starting hard at different lengths of time from shutdown. Happened twice to me now.
