93-02 V6 Tech V6 Camaro General Topics.

random misfire

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  #1  
Old 01-25-2009, 09:27 AM
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Question random misfire

Ok heres the story, i took my car to the wash to get all the road salt off the car,(drive thru undercarriage wash) so im in there getting washed and the idle starts getting rough (no problem it always did in the drive thru) so i drive off and it goes away like every other time BUT....now any hill under light throttle bucks a little so i press a little more on the pedle and it drops in passing gear i hold steady for like 2 seconds and it clears up and takes off. so its friday 01/23/09 lunch time at work and i start the car ses light is flashing random misfire is on the code reader so i take it home to try to fix it, no luck. heres what ive do thus far.....checked all connections to all sensors, removed icm and coils. coils are .7 or better checked all plug wires no burns. so what i want to know is or what im thinking is some how water got some where and is goofing things up like crank sensor or cam sensor any help to keep this poor boy out of the dealer would be great thanks.
 
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Old 01-25-2009, 10:24 AM
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It would help if told us what engine & year.nIf the car runs rough when in the car wash, it is a good indication that the ignition is getting wet, which is not a good thing.
 
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Old 01-25-2009, 10:26 AM
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Originally Posted by z28pete
It would help if told us what engine & year.nIf the car runs rough when in the car wash, it is a good indication that the ignition is getting wet, which is not a good thing.
ok sorry 1998 v6 camaro all stock auto thanks.
 
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Old 01-25-2009, 12:02 PM
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Exclamation misfire random

Originally Posted by hevymetalg
Ok heres the story, i took my car to the wash to get all the road salt off the car,(drive thru undercarriage wash) so im in there getting washed and the idle starts getting rough (no problem it always did in the drive thru) so i drive off and it goes away like every other time BUT....now any hill under light throttle bucks a little so i press a little more on the pedle and it drops in passing gear i hold steady for like 2 seconds and it clears up and takes off. so its friday 01/23/09 lunch time at work and i start the car ses light is flashing random misfire is on the code reader so i take it home to try to fix it, no luck. heres what ive do thus far.....checked all connections to all sensors, removed icm and coils. coils are .7 or better checked all plug wires no burns. so what i want to know is or what im thinking is some how water got some where and is goofing things up like crank sensor or cam sensor any help to keep this poor boy out of the dealer would be great thanks.
bump please help must get to work monday!!!
 
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Old 01-25-2009, 01:31 PM
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Exclamation help please

Originally Posted by hevymetalg
bump please help must get to work monday!!!
help please
 
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Old 01-25-2009, 03:21 PM
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Exclamation help!!!!

Originally Posted by hevymetalg
help please
anybody?
 
  #7  
Old 01-25-2009, 04:07 PM
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Random misfire means just that. Being hat you probably got th ignition wet, I would suspect:
Wet wires, especially around the connectors
Cracked plug due to cold water going against hot plug insulator
One or more coils failing
Ignition control module under the coils failing

Usually random misfire is the result of a lean fuel mixture, but in your case I suspect an ignition problem, because of your car wash experience. Try spraying the wires with WD40 or ignition wire drier to get all the moisture out. Otherwise, my other suggestion is to have the coil packs, and especially the ignition control module tested.
 
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Old 01-25-2009, 05:13 PM
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Originally Posted by z28pete
Random misfire means just that. Being hat you probably got th ignition wet, I would suspect:
Wet wires, especially around the connectors
Cracked plug due to cold water going against hot plug insulator
One or more coils failing
Ignition control module under the coils failing

Usually random misfire is the result of a lean fuel mixture, but in your case I suspect an ignition problem, because of your car wash experience. Try spraying the wires with WD40 or ignition wire drier to get all the moisture out. Otherwise, my other suggestion is to have the coil packs, and especially the ignition control module tested.
ok sounds good,here is what i found out:
I did change all the plugs and it fired right and idles perfect now but under load it still throws the random misfire code. the passenger side plugs were all gas and wet looking the driver side was dry if that sparks someones mind let me know?
 
  #9  
Old 01-26-2009, 01:22 PM
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I really think it's your Ignition Control Module. I had a similar problem and it got worse. The ICM eventually failed outright and left me stranded in the boonies. Thankfully I had AAA and they came and got me. '93 V6 with 210,000 miles at the time. The misfires happened under load as well, similar to your case. Also similar to your case it began after a chassis wash in the drive through car wash. Never again. I suspect what happened was that water got somewhere in the ignition system, not necessarily the ICM creating an intermittent short. The extra load created by the short on the ICM burned it out. Unfortunately in this case you may not find it until something just fails. You changed the plugs, did you change the wires? As they heat up the resistance increases in the wires and if they are borderline one could fail intermittently. I'd try that next and hope for the best. Also be sure to put Electrolytic tune up grease in both wire sockets before attaching them to the plug or the coil terminal to ensure contact at all times and to help prevent contamination in the future. Hope this helps. Be sure to let us know what you find out.
 
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Old 01-26-2009, 06:51 PM
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Originally Posted by TomS68
I really think it's your Ignition Control Module. I had a similar problem and it got worse. The ICM eventually failed outright and left me stranded in the boonies. Thankfully I had AAA and they came and got me. '93 V6 with 210,000 miles at the time. The misfires happened under load as well, similar to your case. Also similar to your case it began after a chassis wash in the drive through car wash. Never again. I suspect what happened was that water got somewhere in the ignition system, not necessarily the ICM creating an intermittent short. The extra load created by the short on the ICM burned it out. Unfortunately in this case you may not find it until something just fails. You changed the plugs, did you change the wires? As they heat up the resistance increases in the wires and if they are borderline one could fail intermittently. I'd try that next and hope for the best. Also be sure to put Electrolytic tune up grease in both wire sockets before attaching them to the plug or the coil terminal to ensure contact at all times and to help prevent contamination in the future. Hope this helps. Be sure to let us know what you find out.
im looking for some good wires and im changing the ALL this weekend
 


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