I just want to know where the speed control vacuum control circuits is on my 1996 Dodge Magnum dakota pickup truck is.

In this link

https://www.google.com/search?q=1996+Dodge+Dakota+with+3.9+L+engine.+Vacuum+lines+diagram

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It is in the link, but also click on the images tab for more.

https://www.google.com/search?q=1995+Dodge+Dakota+5.2L+V8+magnum+vacuum+lines+diagram

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Chrysler Fault Code 41: Alternator field control circuit open ...

www.allpar.com/fix/codes/faults/code-41.html
Possible reasons for Chrysler fault code 41: Alternator field control circuit open or shorted. ... allpar, the Chrysler - Dodge - Plymouth - Jeep site. Note: Allpar ... FauxPar: Return of the Barracuda, 1987-1996 Dodge Dakota pickup trucks, Pinner: ...

1991 and older non magnum engine do not have one. They use only the distributor pickup coil.

Hi Tnmcat,
Check the available vacuum at a manifold port with the engine idling. It should be 17-21 inches of vacuum. If it is to low,it will give you multiple vacuum concerns. Also, I don't think this unit had a vacuum advance. This timing and advance should be controlled by the on board computer (or PCM). If you turn the distributor it will not change the timing but it will throw the fuel system out of synchronization. Here is the vacuum diagram I have. If you need anything else,drop me a line. Thanks,Chuck

change the blower motor resistor. somewhere behind the glovebox area. they are around 20 bucks. common failure.

25 Automatic Idle Speed (AIS) motor driver circuit shorted or target idle not reached, vaccum leak found 53 Logic module internal problem


have you tried to reboot the ECU by removing the pos battery terminal for a few minutes

Sounds like a defective speed control resister.

Not knowing your truck, I'm not sure what Dodge calls it but there is a device that monitors the ambient temperature and sets the fuel-air ratio accordingly.
The "Idle air control" can be used for this in some makes. If this or some part of it has failed, the mix is probably not getting enriched enough to ensure reliable cold starting.  

It could just be your oil filter.
But most likely a weak pump, or a clogged pickup screen in the oil pan