THE CAR HAS A 3

Tiny
WWHEELS
  • MEMBER
  • 1991 BUICK REGAL
  • 120,000 MILES
THE CAR HAS A 3.1 LT ENGINE WHICH WILL NOT START, STARTER TURNS ENGINE OVER, BATTERY VOLTS 12.5, IGNITION MODULE HAS BEEN REPLACED AND IS GETTING 12.5 VOLTS, NONE OF THE 3 COIL PACKS IS PRODUCING A SPARK, RESISTANCE ON EACH COIL PACK IS ABOUT THE SAME, WHAT SHOULD I CHECK NEXT AND WHAT MIGHT BE THE MOST LIKELY PROBLEM?
Sunday, November 18th, 2012 AT 7:08 PM

8 Replies

Tiny
JDL
  • MECHANIC
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Did you check for voltage and ground at the ignition module. Pink wire is voltage goes hot with the key on. Black wire is ground. With bypass ignition, it is the ignition module that controls spark, but, the ignition module has to receive signal from crank sensor, during cranking.
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Sunday, November 18th, 2012 AT 7:20 PM
Tiny
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I meant to say the ignition module controls spark during cranking.
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Sunday, November 18th, 2012 AT 7:21 PM
Tiny
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YES I CHECKED THE VOLTAGE AND GROUND ON THE IGNITION MODULE CHECKED GOOD
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Sunday, November 18th, 2012 AT 9:20 PM
Tiny
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I have also replaced the ignition module
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Sunday, November 18th, 2012 AT 10:02 PM
Tiny
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What about the crank sensor? I hate to see you throw parts, but, my thought was the crank sensor.
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Monday, November 19th, 2012 AT 3:07 PM
Tiny
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How do you check the crank sensor and where is it located on the engine?
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Monday, November 19th, 2012 AT 11:38 PM
Tiny
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I believe it is located on backside of engine down low. May have to get at it from underneath. I wouldn't try to test it, if that is the original crank sensor, I'd replace it. Usually the crank sensor is a lot cheaper than the ignition module. If I narrow it down between the crank sensor and ignition module, I always change the crank sensor first.

If you have a scanner that shows live engine data. Crank the engine and look for an rpm signal. That signal comes from crank sensor. Without that signal, no spark and no injector pulse.

An intermittent rpm signal can drive you crazy.
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Tuesday, November 20th, 2012 AT 12:52 AM
Tiny
JDL
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Here is some testing info.
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Tuesday, November 20th, 2012 AT 1:04 AM

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