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Old Nov 19, 2018 | 10:02 AM
  #16  
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Originally Posted by Mark Kovalsky
That's what you need to diagnose this. It is almost certainly the torque converter locking and unlocking. And no, that doesn't mean the converter is bad. This problem is usually caused by bad data getting to the PCM, which then tells the converter to unlock.
would that work with iPhone as well? What could cause the bad data?
 
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Old Nov 19, 2018 | 10:17 AM
  #17  
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Originally Posted by Cole Eakle

would that work with iPhone as well? What could cause the bad data?
The electrical connection to the trans.
 
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Old Nov 19, 2018 | 10:19 AM
  #18  
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Originally Posted by Dan V
The electrical connection to the trans.
how would you fix that problem?
 
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Old Nov 19, 2018 | 10:49 AM
  #19  
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Originally Posted by Cole Eakle

would that work with iPhone as well? What could cause the bad data?
iPhone is limited with Torque Pro, as I recall. I don't think it does much - if anything - with Forscan, either.

A used Nexus 7 makes for a nice Torque Pro digital dash. But if I could only pick one, it would be Forscan on a laptop with a USB-cabled OBDII adapter. No messing with wonky Bluetooth or wifi connections - hardwired, baby. Forscan does a whole lot more than Torque Pro in the diagnostics department, but digital dash is something it lacks.

The codes you read from Forscan *may* help you diagnose the communication problem, and in combination with the shop manual set, you can see the wiring diagrams and do the pinpoint tests to find the culprit. Some people have excellent success guessing and swapping new parts in, I'm not lucky like that and usually have to go through every step in the shop manual before finding the issue.

My *guess* is a bad connector or shorted harness somewhere. Intermittent electrical issues are simply a drag to diagnose unless you're one of those lucky people.
 
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Old Nov 19, 2018 | 11:23 AM
  #20  
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Originally Posted by PrescottIce
iPhone is limited with Torque Pro, as I recall. I don't think it does much - if anything - with Forscan, either.

A used Nexus 7 makes for a nice Torque Pro digital dash. But if I could only pick one, it would be Forscan on a laptop with a USB-cabled OBDII adapter. No messing with wonky Bluetooth or wifi connections - hardwired, baby. Forscan does a whole lot more than Torque Pro in the diagnostics department, but digital dash is something it lacks.

The codes you read from Forscan *may* help you diagnose the communication problem, and in combination with the shop manual set, you can see the wiring diagrams and do the pinpoint tests to find the culprit. Some people have excellent success guessing and swapping new parts in, I'm not lucky like that and usually have to go through every step in the shop manual before finding the issue.

My *guess* is a bad connector or shorted harness somewhere. Intermittent electrical issues are simply a drag to diagnose unless you're one of those lucky people.
thank you! Is there any way you could send the link to that divice?
 
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Old Nov 19, 2018 | 12:56 PM
  #21  
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Cole...these trucks aren't getting old....they ARE old. You could have corrosion in the connector, a broken wire making intermittent contact..any number of things. Time to get under the truck and get your hands dirty.
 
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Old Nov 19, 2018 | 01:30 PM
  #22  
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Could a spliced overdrive wire cause it?
 
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Old Nov 19, 2018 | 02:26 PM
  #23  
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Originally Posted by Cole Eakle

thank you! Is there any way you could send the link to that divice?
This is the USB device I bought. It won't work on a phone or tablet, as far as I know, but it is as trouble-free as things are going to get when connecting to a laptop:

Amazon Amazon

Forscan:

https://forscan.org

If you're going the Torque Pro route, there are plenty of ELM327 bluetooth and wifi OBDII adapters out there... some are problemmatic, best to look at the Torque forums and see what recent users recommend. They're usually under $30 on eBay or Amazon.

A set of shop manuals on CD is around $36... they are more difficult to follow than the paper version (for me), but the price is right. This is the guy I bought mine from, and I am not unhappy with them:

https://www.ebay.com/itm/2002-FORD-E...72.m2749.l2649
 
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Old Nov 19, 2018 | 04:10 PM
  #24  
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Originally Posted by Cole Eakle

would that work with iPhone as well? What could cause the bad data?
I don't know about the iPhone.

Bad data can come from a bad sensor, bad wiring, a bad brake light switch, and about 50 other things.
 
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Old Nov 19, 2018 | 04:13 PM
  #25  
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Originally Posted by Cole Eakle
how would you fix that problem?
Remove the electrical connector from the passenger's side of the trans. Find out where the corrosion is and then fix it.
Originally Posted by Cole Eakle
Could a spliced overdrive wire cause it?
I don't know what an overdrive wire is. Any modification to the wiring can cause issues such as this.
 
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Old Nov 19, 2018 | 04:33 PM
  #26  
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Originally Posted by Mark Kovalsky
Remove the electrical connector from the passenger's side of the trans. Find out where the corrosion is and then fix it.

I don't know what an overdrive wire is. Any modification to the wiring can cause issues such as this.
okay I’ll get under and look. Here’s a video of it.


Is this the wire?
 
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Old Nov 19, 2018 | 04:44 PM
  #27  
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I have a video of it doing it but I can’t figure out how to post it
 
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Old Nov 19, 2018 | 04:54 PM
  #28  
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Originally Posted by Cole Eakle
I have a video of it doing it but I can’t figure out how to post it
The speed of the truck doesn’t fluctuate while I’m driving either and it does this
 
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Old Nov 19, 2018 | 04:56 PM
  #29  
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Originally Posted by Cole Eakle
I have a video of it doing it but I can’t figure out how to post it
Post your video to YouTube then link it here.
 
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Old Nov 19, 2018 | 05:05 PM
  #30  
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https://m.youtube.com/watch?v=PJzQ9u...ature=youtu.be

heres the video and watch the rpms.
 
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