Year of truck: 2000

Motor: 5.9 Cummins

Mods: None...

However, I just had the AC guy evacuate and refill the AC to his spec. 

How is the truck primarily used: Just used to go to work, however, i recently purchased the truck from a guy that wasnʻt using it much. Seems like it was sitting for quite sometime. 

When did the issue start, and if it's intermittent or all the time: The truck turned off last week thursday, and restarted easily. On friday(7/22) i parked it on a hill(running) and it died. I rolled it down and on the side of my house and now it wonʻt start. It throws a P0123 and P1639 code and wont start for sh!t. I can hear the Lift Pump priming, and hit the schrader valve on the IP to see what the pressure looks like -it kinda trickles out. Havenʻt yet checked fuel pressure, but will do it asap. Also, I tried to reset the APPS because thats what iʻve been told the P0123 code is, but nothing. No start, lots of crank. While I tried to start, I cracked the lines at 1 and 3 and no fuel is coming out of there...

Darn truck sent no warning signs or hiccups. Has been running strong until it went Kaput!

 

 

So, today, I checked the truck out, cycled the key, and the lift pump cycled. Replaced the lift pump, and now... NO CYCLE! When I was replacing the lift pump, I noticed the fuel line was rather dry. The in and out lines both leaked no fuel which is rather odd, given the last time I replaced a lift pump, I lost some fuel. I am dumbfounded that the cycling is not happening...

 

Thank you all in advance for your help...

Aloha,

Andrew

 

 

gonna go through the P0123 code diagnostic... Damnit, wish there was a plug and play fix...

You done nothing to fix the APPS P0123 code.

 

Possible Causes

• 5-volt Supply At APPS Shorted To Voltage (Engine Running)
• APPS 5-volt Supply Circuit Shorted To Voltage
• APPS Signal Circuit Shorted To Voltage (Engine Running)
• APPS Signal Circuit Shorted To Voltage
• APPS Return Circuit Open
• APPS Signal Circuit Open From APPS To ECM
• APPS 5-volt Supply Circuit Open
• PCM (APPS) Circuit Shorted To Voltage With The Engine Running
• PCM (APPS) Short To Voltage With Ignition Key On
• APPS Open Between PCM And ECM
• Open APPS Circuit
• Accelerator Pedal Position Sensor (APPS)
• Engine Control Module

4 minutes ago, Mopar1973Man said:

You done nothing to fix the APPS P0123 code.

 

Possible Causes

• 5-volt Supply At APPS Shorted To Voltage (Engine Running)
• APPS 5-volt Supply Circuit Shorted To Voltage
• APPS Signal Circuit Shorted To Voltage (Engine Running)
• APPS Signal Circuit Shorted To Voltage
• APPS Return Circuit Open
• APPS Signal Circuit Open From APPS To ECM
• APPS 5-volt Supply Circuit Open
• PCM (APPS) Circuit Shorted To Voltage With The Engine Running
• PCM (APPS) Short To Voltage With Ignition Key On
• APPS Open Between PCM And ECM
• Open APPS Circuit
• Accelerator Pedal Position Sensor (APPS)
• Engine Control Module

Yep, nothing. To be quite honest, the 4th gear hunting was occuring until I died out and never got it back. Is it possible that the APPS just needs to be changed? I donʻt suppose I have dead pedal, the truck is rather smooth throughout acceleration, and it doesnʻt ever hiccup, it just wont shift into OD now...

Gotta go through the diagnostics and see if it point you in the right direction.

7 hours ago, Mopar1973Man said:

Gotta go through the diagnostics and see if it point you in the right direction.

Gonna take on that diagnostic in the morning. Meanwhile, pulled the codes with my scanner, it sed no engine dtcs however, it did say Transmission DTC present P0123.... So what computer is this pulling from!?

The key trick says the same thing

The key trick as far as I know will only give codes from the ECM and the PCM. On your truck you are only getting the ECM. My 02 gets both but not always everything. Thats why we reccomend using a scanner. I have never seen mine identify a trans code. The 0123 code is an apps code. How is you scanner telling you that it is a trans code?

5. Check for poor connection/terminal contact at APPS harness connector. Repair as necessary. Ensure APPS connector is still disconnected. Start engine. Using a DVOM, measure voltage between cylinder block (ground) and terminal No. 3 (Light Blue/Black wire) on APPS connector. If the voltage is greater than 5.5 volts, go to next step. If the voltage is 5.5 volts or less, go to step 8.

 

Voltage is at like 0 on the connector at this wire, i stuck a paper clip in to try and pull the voltage up, and the truck began to rev...

 

i will attach a picture of the scanner

How can you properly do this test with the apps connector disconnected?? You may have to wiggle your backprobe wire around a bit to get a good cennection....

Edited August 7, 20168 yr by leathermaneod

Some of the tests are done with the connector disconnected. The step he lists is to see if the ECM is sending voltage to the apps. The voltage should be present even disconnected.

Some of the test are ohming from point to point. Them the the other test is ohm to ground looking for shorts to ground. so that why it seem weird probing the loom and then ground with both unhooked.

So, every darn Auto Store had a different AC reading on my alt. FOUND A FLUKE AT WORK, gonna check it out!

21 minutes ago, AndrewFrias said:

So, every darn Auto Store had a different AC reading on my alt. FOUND A FLUKE AT WORK, gonna check it out!

 

Remember that auto part store testers test at full load of the alternator. We'll test at resting state idling. So the numbers will be very different. 

Just now, Mopar1973Man said:

 

Remember that auto part store testers test at full load of the alternator. We'll test at resting state idling. So the numbers will be very different. 

Thanks Mike... Appreciate it.

 

Weird, i have fluctuating vac at the alt. And battery ground... 0.040 to 0.050 up n down n up n down...

 

 

Also, AC IS BACK, haven't driven it yet however, im thinking that the bottom bolt of the alt wasnt solid, causing a terrible ground, and power flying throughout the circut!!!  What the heck!

 

 

Seems like AC noise was confusing the PCM, could this be from the loose bolt?

 

if my vac is fluctuating is that bad? I gotta pull some cattle from Hamakua side to Hilo, wanna do it sunday!!!

Just jumped in the truck, no AC again, no OD, im thinking im testing this alternatir wrong... Or i grounded out the alt. Ehen i was testing it which caused everuthing to work properly... For a few minutes.

 Just through the fluke on it and VAC was fluctuating between .050 and .057.  I'm ground the on the fluke at the battery and put in the positive lead on the black wire that's leading to the alternator is this correct?

12 hours ago, AndrewFrias said:

For a few minutes. Just through the fluke on it and VAC was fluctuating between .050 and .057.  I'm ground the on the fluke at the battery and put in the positive lead on the black wire that's leading to the alternator is this correct?

 

 

That is correct but showing a marginal alternator. Should be reading more so below 0.03 AC volts.

 

Normal - 0.01 to 0.03

 

Marginal 0.05 - Some report random and strange issues at this point. 

 

Fail 0.1 and above.