Weird problem. intermitant transmission loss

[bigbird]

Don't know what section this should go in so mods feel free to move it. Couple weeks ago at the track on one of my runs i assumed i had broke a shaft after launch as the trans would not engage. looked down and the gear selector was in D but it was flashing. put truck in neutral and then back in drive and it worked fine. Did 4 more runs and trans acted fine. kind of forgot about it. then today i was driving around and came to a stop sign, when i went to go truck moved a couple feet and then acted like it popped out of gear, i looked and selector was on D but it was flashing again. put truck in reverse and then in drive and it was fine. almost seems like power loss, i found some corrosion. anyone have any other ideas?

 

[bullfrogjohnson]

Maybe the NBSU switch is going out?

 

[MaxPowerLB7]

Any codes?

 

[duratothemax]

pressure switch manifold? sticky e-shift valve?

 

[LBZ]

Any codes?

x2

 

[LBZ]

I'll put this here-Mikey will get ya sorted out!:thumb:

 

[bigbird]

No codes. had my fuel guage suddenly drop to nothing, then come back. shut the truck off and it was completely dead. wiggled the alternator wires, and had power again. cleaned up all power connections and it's been behaving. I'm assuming the power problem and trans problem are related. maybe not?

 

[rgullett83]

possibly Voltage drops and spikes can cause some issues

 

[sweetdiesel]

possibly Voltage drops and spikes can cause some issues

x2 ive had that issue......surprised it didnt code.

 

[heathgu]

Sweetdiesel,

What codes did you get when this was happening?

Cheers Heath

 

[sweetdiesel]

Sweetdiesel,

What codes did you get when this was happening?

Cheers Heath

http://www.duramaxdiesels.com/forum/showthread.php?t=17235&highlight=Record

1760

 

[heathgu]

Thanks mate

 

[01LB7]

double check your batteries, mine did same kind of stuff, threw codes, lost ignition power, lift pump wouldn't work, lost dash lights, gauges................. ended up being two bad batteries

 

[Mike L.]

Call me.

 

[bigbird]

It's an electrical issue. Went to the track and lost power 3 times during the run. Ran 11.2@ 129, came back and the ECM was acting up them truck started arcing and went completely dead. Going to replace all wiring next week.

 

[bigbird]

Still haven't been able to figure it out. Hooked a tech 2 up to it and the only thing it says is high voltage for the fuel guage sensor. i assume i have a bare wire somewhere, but don't know where to even start. any ideas?

 

[LBZ]

Did you end up replacing your harness?
Did you unplug all the trans connections and check for corrosion and stuff?

I'd say start at the fuel tank and start chasing wiring. My guess is that somewhere in the harness where it all comes together and heads up the firewall there are some wires rubbed through.

 

[ZR1160]

I had my fuel gauge stop working once before, it was the ground going the filler neck.

 

[bigbird]

I'm not concerned about the fuel guage working or not, but there are other issues. going to have to do what Dale suggested and start tracing individual wires.

 

[bigbird]

2 of us traced wires for the last 4 hours and found nothing. not sure what to do.