1996 Regal 3800 Series 2 no start continued.

Tiny
PCDJ64
  • MEMBER
  • 1996 BUICK REGAL
  • 120,000 MILES
Can a bad fuel pump cause no spark? No fuel pressure or spark, I mean zero pressure and no coils fire.
if it sits 2 min and almost starts there is 20Psi fuel and good spark and then gone, it sits overnight and the next morning it will run but barely for about 5 seconds then starts the whole thing over.
i was told it could be either the ICM or ECM not the pump. There are no codes coming up, none stored or pending.
i am at a loss with this car, it is a very unusual problem to me.
Saturday, September 1st, 2012 AT 12:45 AM

9 Replies

Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
No. Sparks and fuel pump operations are not causes. They are the result of something not working.

If the crank sensor is not working correctly, there would be no sparks and fuel pump would not work.

Try cyling the ignition switch a few times and check fuel pressure to see if it increases.
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Saturday, September 1st, 2012 AT 10:20 AM
Tiny
PCDJ64
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  • 127 POSTS
Cycling does nothing, it has to sit for a couple minutes before it almost starts again otherwise it just cranks and spraying ether into throttle body does nothing.
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Saturday, September 1st, 2012 AT 11:04 AM
Tiny
KHLOW2008
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When ignition is turned on, the fuel pump relay receives battery voltage from the PCM to operate the fuel pump.

What I need to know is when you cycle the ignition switch (keep it on for at least 2 seconds) does the fuel pump prime during this time and is fuel pressure available?

When there are no sparks, starting fluids would only flood the cylinders and not start up.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Check Item 5 of the above link for more details when sparks are not available.
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Saturday, September 1st, 2012 AT 11:57 AM
Tiny
PCDJ64
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  • 127 POSTS
I do not hear the pump however it does almost start on the first attempt so some fuel is getting through with spark initially, if I immediately try again there is no spark and no fuel and cycling with the key does nothing at all to help it, there is no spark, no fuel, if I turn the key off and wait 2 minutes and then try again it will almost start then fuel and spark goes away again, it sat overnight and the next morning the first try it ran barely for about 5 seconds before it went back to the same routine again.
So the fuel pump only receives the signal once every 2 minutes for enough fuel to almost start the engine before it stops and the spark stops at the same time.
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Saturday, September 1st, 2012 AT 12:10 PM
Tiny
KHLOW2008
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I believe you shoud be testing why there are no sparks.
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Saturday, September 1st, 2012 AT 12:49 PM
Tiny
PCDJ64
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  • 127 POSTS
I would but I need to know why there IS spark and fuel if it sits 2 minutes and not after and why it will run longer if it sits overnight. My testing should be why there is no spark or fuel.
Why does it only almost start after sitting 2 minutes but only cranks after unless I let it sit again, the crank sensor controls fuel and spark, it also sends signal to the ICM so could be a bad ICM too if it is not processing the signal from the crank sensor. Maybe a bad PCM because it is not sending a signal to the pump for enough fuel to actually start the engine instead of ALMOST starting it and losing the signal to both the pump and coils, seems weird that after 2 minutes it tries to start and by cycling the pump does nothing I am aware of since the spark goes away.
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Saturday, September 1st, 2012 AT 12:58 PM
Tiny
KHLOW2008
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You should be diagnosing why and not asking why.
Without a proper diagnosis you would not know why. The testings helps to zero in on the likely cause. It can be anything from a bad sensor to a faulty PCM.
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Saturday, September 1st, 2012 AT 2:09 PM
Tiny
PCDJ64
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I was asking an "expert" so I would have an idea on what to diagnose, someone who knows cars, my bad
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Saturday, September 1st, 2012 AT 2:41 PM
Tiny
KHLOW2008
  • MECHANIC
  • 41,814 POSTS
You were given things to do and you have not provided any feedback on the testings. If you do not want to follow advice, there is nothing we can do to help.

Sorry I am done here.

Have a nice day.
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Saturday, September 1st, 2012 AT 2:53 PM

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