What is the correct name of the little "gizmo" that is between the transfer case and the speedometer cable on my truck and what all does it do? Mine went out on my wife on a long trip and had to make an emergency stop at garage. It was causing it not to shift and the speedometer quit working. They removed it and connected the cable back up. I have been out of state working and havent drove the truck in over 2 months. It is idling high and when I punch it the boost gauge drops. Can it cause any of these problems? Somebody shed some light on this subject for me.

 

When idling? Isnt the boost already at 0? Or is it when you are driving normally, and you hit the accelerator?

 

The speedometer issues have nothing to do with the high idle and boost issues. Your truck should have an electric speedo, it sounds like what broke was the gearbox that corrects for the tire size.

Check the throttle linkage, it may be hanging up causing the high idle.

Explain the boost issue further, I'm confused by what you mean.

 

Yea, I guess I did make that sound confusing. When I am running down the road pulling a slight grade around 60 mph and punch it the boost gauge would drop to around 7 or 8. It usually goes up to 25 lbs. Driving around town it runs fine.