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Every Cylinder Misfiring, Nobody can tell me why

Old Apr 22, 2022 | 05:37 PM
  #11  
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Right, but I had misfires in every cylinder. Rotating my new coils results in misfires in only three. The three that retain the misfire reside on both bank one and bank two. Depending on who you ask. The service manual seems to suggest that cylinders one and five are on the front while I have seen diagrams that suggest one and two are on the front.
On the forums I have seen the layout described as
7 8
5 6
3 4
1 2
(front)

The service manual suggests the layout is
4 8
3 7
2 6
1 5
(front)

I'd love to hire someone as this is beyond my element, but again there is nobody who will even look at the vehicle in the next three weeks within 120mi
 
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Old Apr 22, 2022 | 05:50 PM
  #12  
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How old is the battery, how are your ground points, and what is the voltage when its running? I had tons of rough running and it was attributed to a dying battery with a bad ground
 
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Old Apr 22, 2022 | 06:40 PM
  #13  
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Grounds are clean and functional as far as I can tell.

Running voltage is 14.2. No indication of bad alternator/ bad battery.

As for age, several years. It holds charge well. It holds voltage well. I switched it out with another of equal specs, no gain of function.
 

Last edited by Identamerican; Apr 22, 2022 at 06:47 PM.
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Old Apr 22, 2022 | 07:10 PM
  #14  
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Next thing I would have suggested is fuel pressure but I see you already eliminated that.

Any signs of oil build up in the intake manifold, checked for vacuum leaks I assume
 
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Old Apr 22, 2022 | 07:33 PM
  #15  
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I am at the point where I would be open to considering that there may be low fuel pressure but only when I am not looking. However, being able to limit the misfires through coil rotation would seem to make that unlikely...

The throttle body was not in good condition, it took some serious cleaning before I was satisfied with it. as for the rest of the system, I am happy to pull it out if you think I should do that before pulling the valve covers. I now have several 10mm sockets, two ratchets, a pair of long needle nosed and an extension siting in the engine bay. I'll pull them out from underneath obviously but I lowered the front suspension so I could work on the engine. I'd like to postpone raising it until I can start the vehicle at least.
 
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Old Apr 22, 2022 | 07:41 PM
  #16  
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Let it be known I am willing to offer a bonfire, beer, grilled meat, and a bed to anyone willing to help. I am 1hr away from Nashville... PM if interested

There is absolutely no way I can get it in a shop for weeks, my only option is to fix it myself, whatever it may be. I just need to know what it is.
 
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Old Apr 22, 2022 | 08:12 PM
  #17  
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You can check for oil build up when the throttle body and adapter are off. It would have to be a pretty good accumulation to get to that point.

Did the throttle body have a lot of build up or?
 
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Old Apr 22, 2022 | 08:29 PM
  #18  
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Significant build up to warrant immediate cleaning but not significant enough to cause global misfire, I have confirmed it is operating... correctly I believe, as the guy I recruited to help could see it open and close.
 
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Old Apr 23, 2022 | 07:23 AM
  #19  
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Probably wouldn't cause your misfires, but after cleaning the throttle body, you do need to reset fuel adaptations so the system can do a throttle body relearn.
As far as grounds, have you checked them all? The major ones are battery negative to body, and the engine chassis to body, which terminates under the right front fender well. You can check the chassis ground by running a jumper cable from engine to body. Same for checking the battery ground, run a jumper from battery to body...
I'd get a scope on it and observe the waveforms of your coils when they're firing. You might have gotten some bad coils, have a bad signal going to them, and your fouled plugs could be causing a problem too.
 
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Old Apr 23, 2022 | 11:55 AM
  #20  
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Don't know if it would cause the misfires but based on the oil on the throttle body, did you swap in a new PCV valve? 5 min and less than $50. Theoretically it could cause a vacuum leak and definitely would make your throttle body and manifold dirty by letting oil get in.

Any water get into the passenger side? Maybe some corrosion on the CJB or the wire looms under the passenger sill?
 
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