Engine/Transmission (1998.5 - 2002) 2K dually takes off in 3rd gear

[JLittle]

I Have a 2000 dually auto 5. 9 cummins, that I built back from a wiring fire. I used the original pcm but had to change the ECM engine computer (got original Part #s too!) that came from a std shift truck, I have driven it around 30 miles and it shifts through the gears right until you come to a stop and then would only take off in 2nd and shift right afterwards! so today I changed the oil and antifreeze and took battery cables off for a few hours and started to drive it again and it will only take off in 3rd gear and shift to overdrive ! some one told me that I need a computer reflash? would this cure my problem? what does a reflash do? is there a paticular reflash that I need? I have also checked all my connections etc and its not showing any check engine codes on my OTC and the trans fluid is not getting hot! I hope someone can help, thanks for reading this ad!

 

[fox]

It is going into limp home mode.

Get the codes read.

It could be the gov. pressure sensor and or the transducer. They are on the valvebody, you must drop the pan to get to them.

Could be other things?

 

[JLittle]

The Check engine light is NOT on and my OTC hand held shows no codes or Pending codes either.

 

[BarryG]

I may be all wet here and am certainly no transmission expert so take this fwiw but... I think one thing that causes or can cause this problem is electrical noise. I cannot remember which wire it is but it goes to the transmission and runs along some other wires in the harness that introduce crossover noise to the transmission wire. DTT sells a noise filter for that wire. A call to DTT might give you some good ideas on the exact wire I am thinking of as well as some other ideas on where to look. Also on some aftermarket trannies they need to put in a variable resistor to control the voltage on I think it is the same wire to alleviate the same type problem.

 

[justinp20012500]

Its the orange wire in the middle connector. Located on the PCM on the firewall on the passenger side. You can call Transgo and they will mail you out the resistor. (Thats only if it the governor pressure sensor)

 

[JLittle]

OK I just got a code, gov pressure too high! so I pulled off the pan and fluid and filter, magnet all looked good, I then pulled off a small flat metal plate on the drivers side which is just below a piston with wires comming from it, inside this piston is a spring (similiar to a small engine valve spring) when I pulled spring out I found that the spring is broke in 3 pieces!! whats caused this? I hope someone knows!

 

[OPoole]

call DTT 1 866 504 4002 Bill will know

 

[JLittle]

I called bill and he said to change the gov solnd and sensor and the sping was for the overdrive servo, I changed with all new parts and the truck does the same thing! I dont get any codes now on my otc hand held scanner but I do get some codes when I cycle the switch 3 times, I get p1693, p0713 , they go away when I take off the bat cables, the truck runs very sluggish when this happens just after you start truck up and it also puffs out a blue/white cloud of smoke before it does this too! could the boost map sensor cause this problem? or the PCM? im lost!!!!! I hope someone can help me out? thanks for reading this post!