BIG85JEEP

Truck:
1998.5 24 Valve 2500 QC LB 4x4
Edge Comp - Non tapped VP44
NEW Blue Chip VP44
NEW Batteries

Codes:
p0122
p1693 (obviously)
p1682
p0720
p1765

Problems:
Speedo bounces all over the place when truck is sitting still
Dead spots in the throttle
Trans TQ goes in & out of lock-up
Bucking and stalling when above problems are occuring and I attempt to accellerate

All the codes show a low voltage signal to their respective sensors. I had the alternator checked and it checks out fine...HOWEVER the voltage meter on the dash keeps dropping.

Is my voltage regulator bad?

Side note:
Before these problems, when I would start the truck the voltmeter would be just to the negative side of vertical; it would come up slowly then the interior lights would dim and it would go back down....then the lights would pick back up and so would the guage. It would do this for a few minutes and I assumed it was flip flopping between batteries "topping" them both off....then I ealized I was the only guy having this issue.

My thoughts:

Voltage regulator is bad, not allowing the batteries to charge or allow sufficient voltage out of alternator to truck sensors.

Help,,,,please

Shovelhead

Did you reset the APPS (accelerator pedal position sensor) when you changed the VP-44?
https://www.dieseltruckresource.com/...t-t120532.html
Some of that is normal for a Cummins on cold starts.

Mike L

Quote:

Originally Posted by BIG85JEEP

Side note:
Before these problems, when I would start the truck the voltmeter would be just to the negative side of vertical; it would come up slowly then the interior lights would dim and it would go back down....then the lights would pick back up and so would the guage. It would do this for a few minutes and I assumed it was flip flopping between batteries "topping" them both off....then I ealized I was the only guy having this issue.M

I'm pretty sure that this is not an issue and is common to our beasts. I believe that the dimming lights, fading and recovering voltmeter are just signs that the heating grids, post startup, are working to bring the manifold up to temperature. IIRC as soon as engine temp gets fully up OR the vehicle speed gets over 15mph that particular circuit shuts itself off.

Somebody jump in here if I am wrong!


Cheers!

Mike

BIG85JEEP

It has yet to be under 90 degrees fahrenheit when I am experiencing these symptoms...not exactly a "cold" start

Shovelhead

A faulty Intake Air Temp Sensor could be causing the grid heaters to cycle.......

Try TOTALLY disconnecting the Edge Comp box.
Mine went Tango Uniform one day about a year ago and the truck acted like it wanted to roll over and die even at highway speeds.
Unhooked it, and all's been well since.

BIG85JEEP

I'll try this tonight....I'll try anything to avoid buying a new ECM

nickg

I'd disconnect the power wire on the drv side battery that goes to the grids, grids use 95amps each, and the grid relays are known to stick on killing batterys and alternators

my grids a have been hooked to a manual switch for a couple yrs now, ever since it cost me a couple hundred dollars to replace the batterys, and the replacement relays were 160$ which added insult to injury, so I used 2 ford starter relays instead,

gcdodge

Have you checked the batteries themselves a bad battery will cause all kinds of problems. could have 1 with a dead cell

Mule Skinner

My comp box threw all kinds of codes and truck would run sluggish then run fine, very intermittent problems, unhooked comp and all is good. Edge products, like anything else I guess, can have problems.

BIG85JEEP

I'll try all of the above after work and report back. Thanks guys!

BIG85JEEP

I've been working late and haven't had time to monkey with thte truck (secondary vehicle) so maybe this weekend.

Do any of you have a thought on the voltage regulator? I just don't see how the Edge box or grid relays would keep the alternator from charging.

nickg

grids draw 95amps eachX2 =190amps your alt only manages 140amps!!
so yes if the grids are stuck on the batterys will run down quickly
voltage reg is inside the PCM,

its normal for the voltage and your lights to dim/bright, especially if its colder out as the PCM detects IATtemp and will cycle the grids accordingly (up to 2 mins or until your doing 20miles an hour or so)

is also possible your voltgauge is faulty use a multimeter to confirm battery readings

diconnecting grid power eliminates that as a possible issue

with all the other issues you posted, you need to find and clean all grounds/and battery terminals

also note check alt output right at the alt terminal then compare that reading with your voltage at the batterys.

have also seen wiring burned off right at the alt where the wiring lays against the alt case

BIG85JEEP

I had a chance to mess with it today. Disconnected the grid at the grid and started the truck; alt recovered instantly to 14 volts with no cycling of the grid. Put the meter on the terminals that attach to the grid and there was no voltage. Hooked everything back up drove the truck and have no problems

?????

Could the relay just be "sticky"?

nickg

the relays are super small for the load they carry, and once they arc together its all over, if they stuck on once consider them garbage, because they will stick again when you least expect it.
its easier to leave all the wiring for the grids hooked up, and just unhook the small wires (2 wires with one lug)at the drivers side battery positive post, this wire(s) are the feed to the relays, with this unhooked, there is no chance of the grid wires (if you unhooked them somewhere else) touching ground.

to test to see if your grid relays are stuck on (they are located under drv side battery on fender) with the positive feed wire disconnected. use your multimeter to see if there is continuity between the two large lugs on the relay, if there is they are stuck on, and will need to be replaced...

I unhooked mine as mentioned above because once it started getting cold in the fall, even if the engine was up to operating temp, every hot re-start would cause my grids to cycle for two mins, I had even replaced the IAT sensor, but it still cycled my grids, my truck was used commercially so for me that was a huge amount of electrical load on my alternator, that I did not want or need.

mine are now manually controlled, and I never worry about the grids sticking on, either from the relay or the PCM telling them to turn on.
the wait to start light(WTS) still functions like it should, only difference is I hold the switch down until the WTS light goes out.

I would disconnect the grids, clear all codes, run the truck again and see what codes return, then address any of the returning codes

BIG85JEEP

Thanks Nick, I'll get on it again tonight.

I appreciate the help!

Jeff