In park I noticed that when HIM is on I have more boost pressure than when I (HIM off) put the throttle at 1,200 rpm... And when I have my foot at 1,200 rpm and then put HIM on, the rpms drop. Another situation I had HIM on with my foot holding the eng at 1,400 rpm and then turned HIM off and the rpms when up.

Is this because of the turbo boosting? and/or is there more going on?


Thanks

 

By "high idle mod," do mean SEIC or BCP or some home made circuit? Since SEIC and BCP are factory programed up idle circuits, I wouldn't call either a high idle "mod."

 

How much boost pressure? You should have nearly zero boost when in park, regardless of RPM.

 

it is less than one pis. it jumps between .5 and .7 acording to the insight.

HIM on it will be ~2psi and if I give it throttle to go up to 2,000 rpm it will be ~ 4psi. then if I turn HIM off and go through the rpms the highest I will see is ~1.5psi.

 

I wonder if you did the SEIC or the BCP? Just guessing here, but with SEIC it locks the torque converter and is designed to provide power to a take-off device. That would require some boost. With BCP it is just idle to drive the alternator. No boost needed. Other than that, I cannot explain the behavior you are seeing.

 

What are the wire colors? pics?

 

BCP = Purple/Green Stripe
SEIC = Solid Orange

from here:
http://www.thedieselstop.com/content...%20High%20Idle

 

thank you