1999 Jeep Cherokee ENGINE STARTS BUT DOES NOT FIRE!

1999 JEEP CHEROKEE
150,000 MILES • 4 CYL • 4WD • AUTOMATIC
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JORGE RIVERO
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  • 2 POSTS
HI, COULD YOU TELL ME WHY MY1999 JEEP'S ENGINE WILL TURN OVER BUT NOT FIRE? I CHANGED THE COIL AND THE SPARK PLUGS ARE GOOD. i AM THINKING IT MAY BE THE CRANKING SENSOR BUT I AM NOT SURE HOW TO ACCESS SENSOR ANY SUGGESTIONS?
THANKS JR.
Jun 28, 2008 at 7:01 PM
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BLACKOP555
  • CAR REPAIR CONTRIBUTOR
  • 10,386 POSTS
buy a decent spark tester and check for cranking spark at all cylinders.

get back with the results.

if you have spark it should be bright and blue and not erratically firing either!

you could also dump gas down the throttle body or spray starting fluid down it and have somene attempt to start it, does vehicle run?
Jun 28, 2008 at 8:43 PM
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JORGE RIVERO
  • MEMBER
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I have tried all that you have suggested and even changed the coil, still no spark or fire ....what can I do?

thanks JR
Jun 30, 2008 at 8:01 PM
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BLACKOP555
  • CAR REPAIR CONTRIBUTOR
  • 10,386 POSTS
while cranking the engine are you getting a rpm reading on the tachometer/rpm meter if you will?

if your not getting a rpm signal you either have a bad ignition primary circuit failure or crank shaft sensor failure.
Jun 30, 2008 at 9:48 PM
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