P3400 Code When MDS Kicks On

[NoShoes]

Howdy

I own a 2011 Ram 1500 SLT with a 5.7, I get the P3400 code when my truck tries to activate MDS on the hwy. Do y’all have any suggestions on tuners or something to stop this from happening? I've just been activating my tap shifter and putting it in the highest gear, the code hasn't came back since I've been trying this.

Thanks in advance.

 

[David H]

I've just been activating my tap shifter and putting it in the highest gear, the code hasn't came back since I've been trying this.

That deactivates the MDS so you won't be seeing that code.
I might start with the simple first. Check oil level. Low oil level/pressure may cause this issue.

Any other codes?

 

[NoShoes]

That deactivates the MDS so you won't be seeing that code.
I might start with the simple first. Check oil level. Low oil level/pressure may cause this issue.

Any other codes?

The oil level is fine and the pressure at idle and at 3k rpm is all within the acceptable window, sure on the lower side because my motor has 300km+ on the motor.
Multiple misfires in cylinders 1,4,6,7. From my understanding those are the cylinders the deactivate with MDS.

 

[David H]

Multiple misfires in cylinders 1,4,6,7.

That adds a bit to the stew but I would continue with simple checks for the MDS issue.
Air filter clean, MAF sensor functioning and intake manifold bolts tight.
After that it's likely above my paygrade. Smart guys will chime in shortly.