Engine/Transmission (1998.5 - 2002) 12V into 24V truck charging issue

[BigPapa]

Today in the continuing saga of putting a 12V engine in a 98. 5 24V truck, I have discovered something new.



The issue has been that the alternator doesn't charge immediately after start up. It will start charging under these 3 conditions:

1. If you let it sit there and idle it will start charging on it's own after a couple of minutes which is hard on my batteries when it's cool due to the heater grid cycling.
   
2. After you start rolling and get to @ 20mph and the transmission will shift into 2nd. (This is another issue, the very first trans shift after start-up isn't right. It's sudden and hard at @ 20 mph. After the first time it's perfect until you turn the truck off again. )
   
3. And this one I just discovered. I have always had to give the truck a little throttle pedal to start or it cranks and cranks. Well, I recently adjusted my governor springs to correct a stalling problem when the air is on and you drop it in gear (The 12V was in front of a manual in the previous truck and this wasn't a problem). Since the spring adjustment I have found that I can now start the truck without giving it any pedal. When I start it without giving it any pedal the alternator starts charging a few seconds after start-up!
   

So, any ideas on what's wrong? When I first discovered this 3rd situation I hoped that the trans would shift properly that first time, too, but it doesn't. I was hoping they were related.



For anyone who hasn't read about my conversion it's a '95 12V engine in a 98. 5 24V auto truck. I'm running all 24V sensors including a factory 24V crank sensor and APPS. Everything works great and as it should except for the charging issue and the first shift trans issue.



I will be replacing the APPS in the next few weeks which may be the issue. I know it's bad. I put a micro switch in the current one when I did the swap due to the idle validation circuit being bad. It works fine, but now the rest of it is bad and I have TC lock-up issues that I have addressed currently with a manual lock-up switch.

 

[BigPapa]

Been thinking about this. I'm thinking that the idle validation part of the APPS must effect the charging in some way and when I give it some pedal to start, according to the APPS it's no longer idling.



Opinions?

 

[cerberusiam]

The hard first shif tis classic gov transducer\solenoid problems. It could be influenced by the APPS if it is not reading right on the low side. Hard to tello ther ebecuase both have to function correctly or you get weird shifts.



Charging should be completely under ECU control and what is sees for crank and cam sensors info.