Today on the way home my boost went to 0 and the engine quit making its typical turbo noise (afe mega cannon installed so i hear it pretty well). It only lasted for a few seconds. I lifted off the pedal for a few seconds and when it pushed it again it went back to 4-6 lbs. Any ideas on what would have caused this?


It did it this morning so I turned the a/c off and it went away. Maybe that was just a coincidence but something is not right. Any ideas?

 

wastegate malfunction?

 

where is the wastegate located on these trucks? how can I test it? maybe its sticking?

 

No factory wastegate on a 6.7

Did you do the Throttle valve delete? Did you notice if the EGT's went sky high for a sec?

Something similar to this happened on mine before I did the TVD and I suspect it was a partial closing of the butterfly valve.

 

So even with the TV unhooked it would start to move?

 

No this was back when I had the EJA. TV was plugged in, EGR unplugged. EGTS would go sky high and it would run funny. Id plug the EGR back in and it run it for a while and it would go back to normal. I suspected that it was the throttle valve somehow partially closing and for whatever reason the actuator getting plugged back in would cycle it.

Not really sure if that is what was happening, or if it can happen with the Smarty, just bringing it up.

 

WOW, so they dont have a wastegate?

 

No. The VGT uses a variable nozzle ring to control the turbocharger speed/boost by controlling the exhaust side area of the turbo. In a sense its like continually changing housing sizes on the fly.

 

Which is why one must be very careful when raising boost and rail pressure with a 6.7 with full deletes, and having no mods in place (studs, wastegate etc)

It can turn into a Head Gasket All You Can Eat Buffet!

 

Im not sure about the TV. heres what I did when i installed the smarty jr ME

1. I removed the erg assembly and installed the egr block off plate.
2. Then I removed the egr motor from the assembly and plugged the motor back in and tied it up.
3. Then i removed the egr tube and installed the block off plate.
4. After that I unplugged the cooler on the left hand side

To sum it up, the connector on the passengers sides (egr cooler?) is unplugged
The motor on the drivers side is plugged in but the motor is disconnected from the assembly and just hanging there

 

If you are running the ME software you should also unplug the throttle valve







Pictures courtesy of MADS website.

 

Yup.. thats one plug that gets fogotten.

Blake,

Too true, aftermarket gates are a must for any high power levels.

 

As bad as I want to I will not even load any higher than SW3 till I get more supporting mods in place. Just for the sake of my HG and tranny.

 

So your thinking that throttle valve is my problem? What exactly does that do?

No way its the actual butterfly valve for the intake? If you unplug the sensor how would your truck be able to move?

 

Should default to the open position.


BTW, as far as I know anyway...

Throttle valve

Throttle blade

Butterfly valve

All the same thing......