# Random misfire problem

**URL:** <https://community.cartalk.com/t/random-misfire-problem/19114>\
**Category:** Maintenance/Repairs\
**Tags:** cylinder, electrical-wiring, misfire\
**Created:** [September 4, 2008, 7:55pm UTC](https://community.cartalk.com/t/random-misfire-problem/19114 "2008-09-04T19:55:50Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![scatter98](https://avatars.discourse-cdn.com/v4/letter/s/a88e4f/32.png) [@scatter98](https://community.cartalk.com/u/scatter98)\
**Post date:** [September 4, 2008, 7:55pm UTC](https://community.cartalk.com/t/random-misfire-problem/19114/1 "2008-09-04T19:55:50Z")

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I have a 1992 Pontiac Grand Prix that is having problems. I tend to lose the electrical power to two of my cylinders on a regular basis. It generally occurs after the car has warmed up. I have tested the wires with a timing gun, and found that I lose power to cylinders 2 and 5, as this is a DIS system.  
  
  
  
 I have replaced the entire ignition system–starter, plugs, wires, coils, ignition module, crankshaft sensor, and ECU (in that order)–but the problem persists.  
  
  
  
 I am at my wit’s end trying to figure this out. Any help would be appreciated.

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**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\
**Post date:** [September 5, 2008, 2:46am UTC](https://community.cartalk.com/t/random-misfire-problem/19114/2 "2008-09-05T02:46:48Z")

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The same ignition coil serves #2 and #5 spark plugs. Since you’ve changed the ignition system components, all that’s left is the wiring between those components.  
Now, you need someone experienced with wiring to do a careful check of those wires and electrical connectors ----- including grounds and ground wires.