KATOOM

This may help you out. https://www.google.com/search?q=1690...+cummins+p1690

cguyfish

got another 1690 after clearing....As soon as it warms up it starts missing and eventually dies

KATOOM

Did you read up on that link I provided whereby most who experience what you're describing find it to be a CPS.....

cguyfish

What is that?

cguyfish

cam position sensor? I changed that several years ago

cguyfish

Its only doing it after truck warms up........Wouldnt a cps do it at start up also?

KATOOM

According to the threads I was reading from that one link, the CPS can cause missing like you described, amongst other issues. The crankshaft sensor was up until 2000 and the camshaft sensor was from 2001-2002. That said, if your truck is a 2001 then it could be a build date of 2000.

You mentioned replacing the camshaft sensor already. Why? And where was it located. Behind the VP or behind the starter?

cguyfish

I know it was heck.....I think behind vp

KATOOM

Why did you replace it?

cguyfish

been a while but i think I it would not crank back up after i was at grocery in town. friend ( diesel mechanic that was familar with 5.9) told me.. I ordered it across stree at napa and replaced in parking lot....Fired right up.. thats been several years... Im pretty sure it was at front drivers side. Cam shaft sensor.

jrs_dodge_diesel

A bad CPS won't prevent it from starting (unlike the Ford powerstroke). The VP44 only requires 12 Volts to start and idle. Its base timing is fixed since it is gear driven from the crank and because of that, it does not need the crankshaft position on startup in order to know when to fire the injectors.
The little computer on the VP44 (PSG) can function as it's own ECU and run the engine. After startup, and once communication is establised between the PSG and the Cummins ECM, the ECM will start feeding sensor data to the PSG for timing and fuel control.

cguyfish

like i said . Its been a while. I also remember woring on something just above starter...o well....

cguyfish

What is the term AC. in referance to this ...............DTC P1690: FUEL INJECTION PUMP CKP SENSOR DOES NOT AGREE WITH ECM CKP SENSOR
Monitor & Set Conditions

Fuel Injection Pump Crankshaft Position (CKP) circuit is monitored when ignition is on and engine is running. DTC may be stored when no signal exists within specified window parameters with no Camshaft Position (CMP) sensor or CKP DTCs present.

Possible Causes

AC Noise Across Fuel Transfer Pump
Other DTCs Present
Wiring & Connectors
Fuel Injection Pump Static Timing
Fuel Sync Signal Circuit Open
Fuel Sync Signal Circuit Short To Ground
ECM
Testing

1. Measure AC noise to ECM by connecting DVOM between ground and terminals No. 48 and 50 (Red/White wires) at ECM harness connector. If AC voltage is 25 mV rms or less, go to next step. If AC voltage is greater than 25 mV rms, replace fuel transfer pump. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

2. Turn ignition on with engine off. Using DRBIII(R) scan tool, check for DTCs. If no additional DTCs exist, go to next step. If any additional DTCs exist, repair other DTCs first. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .

3. Using scan tool, check Good Trip Counter for DTC P1690. If Good Trip Counter for DTC P1690 is displayed and equal to zero, go to next step. If Good Trip Counter for DTC P1690 is displayed and not equal to zero, go to step 5 .

4. Turn ignition off. Disconnect FPCM harness connector. FPCM harness connector is located on end of fuel injection pump. Check for poor connection/terminal contact at FPCM harness connector. Repair as necessary. Disconnect ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Check for poor connection/terminal contact at ECM harness connector. Repair as necessary. Using DVOM, measure resistance of Dark Green wire between terminal No. 8 on FPCM harness connector and terminal No. 18 on ECM harness connector. If resistance is less than 5 ohms, go to step 7 . If resistance is 5 ohms or greater, repair open in Dark Green wire
between FPCM and ECM.

5. Turn ignition off. At this time, conditions required for DTC to be stored are not present. Inspect wiring and connectors between FPCM and ECM. FPCM is located on top of fuel injection pump. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. If no problems exist, go to next step. If any problems exist, repair wiring or connectors as necessary.

6. Check fuel injection pump timing. See CHECKING FUEL INJECTION PUMP TIMING under FUEL INJECTION PUMP TIMING in ON-VEHICLE ADJUSTMENTS - RAM PICKUP - DIESEL article. If fuel injection pump timing is okay, go to next step. If fuel injection pump timing requires adjustment,
adjust fuel injection pump timing as necessary.

7. Ensure ignition is off. Disconnect FPCM harness connector. FPCM harness connector is located on end of fuel injection pump. Disconnect ECM harness connector. ECM is located on driver's side of engine, just in front of fuel transfer pump and contains a 50-pin connector. Using DVOM, measure resistance between ground and terminal No. 8 (Dark Green wire) on FPCM harness connector. If resistance is 5 ohms or greater, replace and program ECM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. If resistance is less than 5 ohms, repair short to ground in Dark Green wire between FPCM and ECM.

KATOOM

I say it so often that I forget which threads I do say it in.....and I think I didnt here.

So.....its VERY important to understand that the Cummins ISB 2nd gen VP engines are completely electronically controlled. Therefor any and all electronic variances which are out of parameters for voltage and amperage will result in phantom issues having you chase your tail.

You must be assured that both batteries are in perfect condition and age and size. Testing them fully disconnected from the truck and each other. Check all major connections for tightness and if road salts are common in your area then check for corrosion too. Make sure all grounds are tight and clean. Make sure the alternator is putting out the correct voltage and isnt making too much AC noise. There's plenty of Youtube videos on how to test this easy check too as all alternators produce "some" AC noise.

Believe it or not but this is more of an issue than you'd think. There's plenty of threads where people tell how their truck runs and shifts amazing after replacing the batteries or alternator. Thats not me saying run out and spend money either but just do some checking.

cguyfish

Thanks so much for helping me start to diagnose... Will start with batteries now.