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bigfootchiro

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Alright guys, here we go! Limped the Hoe from Palm Springs to Largo. Made it 130 miles, and this happened. Couple things to note... it would have a very difficult time locking up the torque converter, so transmission temps would go up to around 210 at times. If TC did lock up, it would misfire and stutter/shake like crazy, Cylinder 3 misfires would go through the roof, and TC would unlock for a while. Truck would literally only misfire when TC would lockup, but knock was there the entire time.

Makes it hard to believe that a rod bearing is bad. I’ve pinpointed knocks and misfires to Cylinders 3 and 8. Cylinder 8 happens at idle once throttle has been touched but once it starts it’s always there. If truck sits at idle after start up, it won’t misfire til the throttle is touched, and Cylinder 8 starts to misfire once idle is reached again. Cylinder 3 misfires mostly when TC is locked up.

Without tearing into the bottom side of the motor yet, what electrical issue could cause this? Bad ground, knock sensor, etc? I replaced the PCM and that did nothing.

 

dubyagee01

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Sounds like a spark to a cylinder has dropped out. Power is down and the ecm is freaking out. Worst case scenario is the torque converter has detonated but the code says otherwise.

I would do a complete tune up and do a compression test while doing it.
 

Tonyrodz

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Damn that sux! I hope you get it straightened out. What happened at the end of the video? Stalled and died? Or did you shut it down?
 
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bigfootchiro

bigfootchiro

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Sounds like a spark to a cylinder has dropped out. Power is down and the ecm is freaking out. Worst case scenario is the torque converter has detonated but the code says otherwise.

I would do a complete tune up and do a compression test while doing it.

I keep leaning back to spark knock too. How would the TC blowing up cause a cylinder 3 misfire? Truck has new cap and rotor, plug wires, I’ve swapped out plugs...

Damn that sux! I hope you get it straightened out. What happened at the end of the video? Stalled and died? Or did you shut it down?

It just stalled and died! I let it sit for ten minutes, and it started right up too
 
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bigfootchiro

bigfootchiro

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Seems electrical to me...

That’s what I keep thinking! But wtf would it be?! Maybe my cap/rotor is fried after only a few hundred miles of use? Bad ground? If it were the coil, all cylinders would misfire, am I correct?
 

east302

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What codes are you getting?

I’ll give you credit, you would have heard me cussing if that was me in the video.


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bigfootchiro

bigfootchiro

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What codes are you getting?

I’ll give you credit, you would have heard me cussing if that was me in the video.


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Hahaha trust me, I was monitoring the trans temps the whole way, and finally when the TC would lockup and the temps start going down, I’d hit a damn red light and would cuss my head off lol. Only codes I were getting during this time were misfire codes and EGR code (I blocked off EGR, but didn’t tune it out). I now have the EGR hooked back up, no code, and still the same is happening. I have two wheel speed sensor codes, but those have been there since the beginning.
 

east302

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Taking a guess, you said the TC was not locking up. Does it have to be in closed loop to lock up? What does your scanner give for the coolant temperature (ECT sensor by the thermostat)?

It wouldn’t hurt to spray the ignition system down with some water at night. If it’s only misfiring on 3 and 8, maybe swap those plugs for another cylinder. Check for spark quality and compression as well.

What brand distributor cap are you using?


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bigfootchiro

bigfootchiro

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Taking a guess, you said the TC was not locking up. Does it have to be in closed loop to lock up? What does your scanner give for the coolant temperature (ECT sensor by the thermostat)?

It wouldn’t hurt to spray the ignition system down with some water at night. If it’s only misfiring on 3 and 8, maybe swap those plugs for another cylinder. Check for spark quality and compression as well.

What brand distributor cap are you using?


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Swapped plugs around and wires, and misfires stayed on 3 and 8. Idk about the TC being in closed loop or not, but I can check ECT temps on scanner. Coolant temps on dash stayed normal the whole time, and it happens throughout all engine coolant temps.

I can’t remember the name, but it came with my Skip White performance distributor (which is not installed).
 
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