High Idle Article - Mopar1973Man.Com High Idle Operation Manual for 2nd Gen VP44 Cummins

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Operating Instructions

Once the high idle kit is installed its ready for use if the ECM has had the High Idle Feature Enabled, the Dealer can enable this feature, or a Smarty can flash the High Idle into the ECM.  There is a Dodge TSB Covering what needs to be done, Dodge High Idle TSB

 

You can view the Install Article Here, mopar1973man.com High Idle Switch Install

you can buy a High Idle Switch in our Store - 

 

General Operation

It's always suggested you set you high idle mode before starting the vehicle. This will insure you going to get the selected mode of operation. If you want to leave it totally automatic high idle then select OFF as it will follow the ECM software for selection. So you should select either 3 CYL or 6 CYL mode before starting.

NOTE: Selecting a high idle mode will enable this mode and remain the set high idle mode for the rest of the key cycle.

Off

OFF is completely stock ECM sees engine coolant temperature and intake manifold temperatures normally.

MPG Mode

MPG mode is a special mode design around extreme cold operation. During winter time the IAT temps will fall to very low temperature. This typically advances timing quite heavily and create quite a bit of engine rattle at cold engine temperature. MPG mode tricks the ECM into believing it's summer time and retards the timing down to a usable level. Most people report at least 1-3 MPG gain from using this mode.

NOTE: Pre-heat grid heater function is disable in this mode.

 

IAT is 143*f 

ECT is a pass through

6 Cylinder Mode

6 CYL high idle is a special mode in which it was fixed to remain in high idle mode as long as the switch is left in 6 cylinder mode. So this makes it an excellent function for like jump starting other vehicles or keeping vehicle warm in sub-zero temperature. As long as the switch is on 6 Cylinder mode it will not cancel.

NOTE: Engine temperature gauge is disabled during the use of this mode.

IAT is 23*f 

ECT is 140*f

 

3 Cylinder Mode

3 CYL mode is automatic mode. It will enable the 3 cylinder high idle but will cancel the high idle mode once 170°F of coolant temperature is reached.

IAT is 14*f 

ECT is a pass through

Selecting High Idle Mode While Running

This is possible but not suggested. If you do opt for this make sure to rotate the knob fast. If you turn the knob too slowly the switch will break the circuit on the IAT sensor for too long and might trip the P0113 code which is IAT voltage too high. It also possible to get the wrong mode of high idle from this issue. So you may select 6 cylinder but end up with 3 cylinder.

 

It is not recommended or supported to use high idle positions other than Off or MPG when the vehicle is in motion.

Canceling Selected High Idle Mode

The only way to cancel a selected high idle mode is to turn off the engine and wait 10 seconds and start again. This will reset the high idle mode. Be sure to set the proper mode you wish to start with either OFF, 6 CYL or 3CYL before starting.   Please note that once ECT temps reach full operating temp the switch can be turned to off and the ecm will not longer high idle.

Safety Systems

All safety system are still in effect for canceling.

• Speed greater than 0 MPH

• Automatic transmission place into gear

• Service brake pedal pressed

• 170°F coolant reached (unless 6 CYL mode is used)

Enhanced Warm Up

For owners with exhaust brake you can enhance your warm up time to under 10 minutes. Select either 3 CYL or 6 CYL modes and set your exhaust brake on. The exhaust brake combined with the high idle will produce higher EGT's which in turn warm the engine faster.

WARNING: Owners with larger than stock injectors be aware EGT's can climb rather high in 3 cylinder mode and can be as high as 1,000 to 1,100°F with a mere +50 HP injectors.

 

You can see the switch in action, notice the ECT and IAT  sensors changing values.

 

 

 

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