Truck randomly dies. Please help, pulling my hair out, and loosing sleep!

[wh82]

So, before you guys tell me to search if this has been answered before, believe me, I've searched this forum and the other Cummins forums to the point where I can't even think anymore I'm soo tired.

 

I've been having torque converter lockups for a long time on my 2001. I've done every rewire out there, even bought the "sponge" (capacitor) from ATS to compliment their transmission and it still doesn't like being in between 30 and 40, you give it any throttle and it jumps back to 3rd and let off and its back into 4th... I've long suspected the alternator but it always tests clean, I'll get to that in a moment.

 

So this weekend, I decided due to excessive smoke and lag with my Edge disabled it was time for injectors. I went with some DAP +75s and Saturday night dug in and got them installed. Following numerous posts and YouTube videos I got through the process since I've never done it before I was a bit worried but it was actually easy (I'll be honest here, I may have skipped over any sort of priming/cracking open fuel lines  (I didn't know) and started the truck up, but it started right up and is really smooth, quieter than ever). Got everything torqued back down. Test drove the truck for about an hour and wow, big difference. I don't even think I need the Edge anymore other than for gauges.

 

Next day (Sunday) we decide to go for a drive, got on the freeway, tons of power, actually fairly scary to be honest about 3/4 through the loop while heading back towards my house the truck dies and then springs itself back to life, however looking at the gauges, I notice no fuel pressure at all... I kill and restart the truck make it to the next stop light and it does it again. Loss of fuel, truck stutters and then springs back to life aggressively!

 

Luckily, I make it back home and first thing I start checking is power to the relay to the fuel pump. It's got power at start, but even just sitting in my driveway, the power just vanishes from the fuel pump causing the truck to stutter and then fire back to life with 0psi on the lift. WTH?

Checking the relays, the weird massively zip-tied wiring job (the pump was installed at the same time as my trans) and 2 unused wires touching the body... grrr.

 

During all this I found the one connector above the valve cover I was just working with and likely bumped.. the one with the gray lock was unlocked and about 1/4 open... as deep as it goes, still probably fine, made sure that and the other connector there were clean and made sure they were locked. Cleaned the fuel pump relay connector (the stock connector that goes to the original pump) and every other connector within my reach including all 3 PCM connectors with contact cleaner and air.

 

At this point I notice my APPS reading on the Edge all over the place, thinking back to all my issues I'm like, "That damn alternator noise" so. I grab my meter and quickly do an AC test... .019 .5, truck stutters 2.5!, .02... well the 2.5 was a fluke apparently because the truck was stuttering.

 

Pissed off, I remove the alternator.. I had not purchased a fancy one that I had planned on like on my other truck yet. I'm shocked to find a Chrysler branded Bosch alternator when soooo many talk about Denso units on their trucks. I went to O-Really?'s and had them test it, their machine measures PASS with .40 ripple voltage (their threshold is 2.5!?) and I went, hmm I want to try something else. I run to AutoZone instead and theirs tested at .45, a brand new one actually tested .55 so I'm like, their machines are inaccurate anyway because of the motor that drives. I take a new unit and an old unit back to the house. I test the old unit's diodes and they are fine so I put it back on for now. Start the truck, now it's like 10 to 15 degrees cooler outside and the truck has been sitting 2 hours since it's last stutter episode and it's fine, it runs just fine... grr and the APPS is reading a nice flat 0% at idle.. however watching it, it eventually crawls up to 5%.

 

I'm at a loss on what to try next, is it just the APPS, can the APPS freak-outs make the whole computer shut the truck down, including dropping the fuel. Am I looking at a dreaded ECM replacement? Is the heat causing the ECM to be intermittent? At this point, I doubt the alternator...

 

TL;DR; Changed injectors, did valve adjustment, next day... It was hot, drove normal even APPS bounces around a bit as usual. truck died multiple times but only when foot off the pedal and came back to life... each time Airdog dropped out, Relays, Alternator, everything else appear fine, truck cooled down and idles fine, but afraid to drive it now.  

[Threadzy]

Wire mods you say? So you have done the W-T wire mod? All grounds checked and thoroughly cleaned? I replace my alternator years ago with a Nations. I still had TC lock and unlock issues until I did the W-T wire mod. No problems since.  Does the wait to start light come on instantly when the key is turned? The ECM powers the lift pump.  So if the ECM is bad that could cause the lift pump to not work. Have you tested the apps with a volt meter to see if it ramps up smoothly when applying throttle? If it needs an apps I would recommend the Timbo’s. A lot of guys on here including myself have them. You can purchase it here on site. 

[Mopar1973Man]

 Need more info...

 

 

1 hour ago, Threadzy said:

Does the wait to start light come on instantly when the key is turned?

The ECM if its not booting up the wait to start will not come on nor will the engine start. 

 

1 hour ago, Threadzy said:

The ECM powers the lift pump.  So if the ECM is bad that could cause the lift pump to not work.

If the ECM circuit for the lift pump is burned up it will not supply power. This is why most switch over to FASS or AirDog and get the protection relay so the power is supplied by a relay and not the ECM. If your lift pump plugs directly into the ECM plug then its very possible for the ECM lift pump circuit to be burnt by a shorted lift pump.

 

1 hour ago, Threadzy said:

If it needs an apps I would recommend the Timbo’s.

We have those in stock...

 

[wh82]

9 hours ago, Threadzy said:

Wire mods you say? So you have done the W-T wire mod? All grounds checked and thoroughly cleaned? I replace my alternator years ago with a Nations. I still had TC lock and unlock issues until I did the W-T wire mod. No problems since.  Does the wait to start light come on instantly when the key is turned? The ECM powers the lift pump.  So if the ECM is bad that could cause the lift pump to not work. Have you tested the apps with a volt meter to see if it ramps up smoothly when applying throttle? If it needs an apps I would recommend the Timbo’s. A lot of guys on here including myself have them. You can purchase it here on site. 

Wire mods such as the apps capacitor or *sponge*, the apps direct re-wire from ATS... and yes, the ground mod.

 

The ECM is definately working, there is no Wait to Start light (I think it's too hot for that) I just drove it today to lunch, its fine until I've driven it for a good 20 minutes or so and it's warmed up. Then, randomly died like 4 times but only at lowwwww throttle, high throttle doesnt effect it. Can the APPS really case the whole truck to shut down? My  friend said my voltage guage dropped to zero a couple times. Oh crap, maybe it's the battery mod... (gonna go bypass that and test drive again...)

 

The alternator has almost zero ripple, the noise i'm reading on 2 meters and my oscilloscope are present when not even connected to the vehicle, so its just atmospheric noise at this point.

 

I saw a really comprehensive APPS test somwhere that was like, check 10 different wires but not sure where i placed the bookmark

Edited July 13, 2021 by wh82

[Threadzy]

Even well over 100 degrees outside my WTS still lights up momentarily. I’m not sure if a faulty apps would cause the engine to die but if the voltage on the apps is randomly fluctuating that’s definitely a problem. When my stock apps went out. All I got was a dead pedal. Have you scanned the truck for codes? 

[wh82]

7 minutes ago, Threadzy said:

Even well over 100 degrees outside my WTS still lights up momentarily. I’m not sure if a faulty apps would cause the engine to die but if the voltage on the apps is randomly fluctuating that’s definitely a problem. When my stock apps went out. All I got was a dead pedal. Have you scanned the truck for codes? 

Every light but that light comes on. I saw it recently. But not since this started. That fluctuation I always have assumed noise and tried absolutely every trick to fix.. so maybe it is just the apps. P0122 voltage low recently plaguing me so did the set screw adjust and recalibrate... But now im also getting p1693 companion code which i can't fully read of course. But many say is the vp44 dieing... 

 

Im in the process of removing the edge and also my agm voltage boost mod.

[Silverwolf2691]

You have a lot of things going on with your truck. I would say remove all of those filters and "sponges" you added then test again. They are a band-aid at best and snake oil otherwise. They could be hiding your issue as well.

 

The wait to start light comes on no matter what as a check that the ecm is booted up. Bar none. so if the light isn't coming on your ecm isn't booting.

 

10 minutes ago, wh82 said:

my agm voltage boost mod.

 

  ummm.. what? care to share with the class?

[wh82]

18 minutes ago, Silverwolf2691 said:

 

  ummm.. what? care to share with the class?

Sure, a little fact about older vehicles, they dont do well with AGM batteries, AGM batteries need 13.8v as a float and 14.5 to 14.8 as a charge voltage, if your alternator is doing less than that, they dont charge and it kills the battery. Same thing applies in any application and its written on the battery. Their resting voltage when fully charged is around 13.3, so when your PCM checks it, it thinks it's full and doesnt send the field signal to the alternator and therefore doesnt really charge your battery fully which over time destroys the AGM battery fast. The best battery to use is a simple flooded, however. I loathe them for many reasons, so there are many ways to fix this, one of which is to "trick" the ECM with a dangerous hack... There's a box you can buy from a company (or two) I won't name that sits inline of your PCM power feed (fuse 3 on a 2001 cummins) It's a little computer chip that makes the voltage read just a bit lower as it passes through to the PCM, so at 14.6v for instance your computer 'sees' 13.8ish (or at least mine does) and at 13.3 it knocks it down to about 12, basically it makes the computer think you have a normal type battery... The advangage of this of course is that the alternator is still PCM controlled, the disadvantage, well, the power to your PCM flows through it, I originally thought it just to be the sense line, but looking at the diagrams, this is the main power feed. Other methods for doing the same include external voltage regulators, but often these just make your alternator always on, which isn't necessarily good for a battery.

[Mopar1973Man]

1 hour ago, Silverwolf2691 said:

You have a lot of things going on with your truck. I would say remove all of those filters and "sponges" you added then test again. They are a band-aid at best and snake oil otherwise. They could be hiding your issue as well.

 

The wait to start light comes on no matter what as a check that the ecm is booted up. Bar none. so if the light isn't coming on your ecm isn't booting.

Absolutely..  remove all the other ground mods.

[wh82]

20 minutes ago, Mopar1973Man said:

Absolutely..  remove all the other ground mods.

I thought everybody said the truck wouldn't start if the ECM wasn't booting... The truck starts and runs and then randomly dies but comes right back.

 

Removing all the ground mods is impossible as original ground wires no longer exist.. Good ground is critical to all vehicles I understand where you're coming from going back to square one but in this case my alternator is fine my grounds are fine... I'm really thinking it's that voltage box...

 

Since I had tried everything else on the APPS for my hunting issue which by the way the capacitor did kind of fix by smoothing out the pedal only... I just ordered an APPS since that's the only thing that has never really been switched. I don't think that has anything to do with my truck dying. And it's really weird to me that the truck dying started after changing my injectors yay for coincidences!

Edited July 12, 2021 by wh82

[wh82]

2 hours ago, wh82 said:

I thought everybody said the truck wouldn't start if the ECM wasn't booting... The truck starts and runs and then randomly dies but comes right back.

 

Removing all the ground mods is impossible as original ground wires no longer exist.. Good ground is critical to all vehicles I understand where you're coming from going back to square one but in this case my alternator is fine my grounds are fine... I'm really thinking it's that voltage box...

 

Since I had tried everything else on the APPS for my hunting issue which by the way the capacitor did kind of fix by smoothing out the pedal only... I just ordered an APPS since that's the only thing that has never really been switched. I don't think that has anything to do with my truck dying. And it's really weird to me that the truck dying started after changing my injectors yay for coincidences!

Oh and the light does come on... Removed my voltage booster and my edge... No change.

[Threadzy]

My VP44 never through a code. The PSG went bad. Wouldn’t start after it hit operating temp. After replacing it  the new one was bad without throwing a code as well.  Would die when going from reverse to drive. It eventually got so bad it would die while driving when I let off the throttle. Was fun when making a turn with no power steering and brakes. The warrantied  one has been flawless over a year now. 

[wh82]

1 hour ago, Threadzy said:

My VP44 never through a code. The PSG went bad. Wouldn’t start after it hit operating temp. After replacing it  the new one was bad without throwing a code as well.  Would die when going from reverse to drive. It eventually got so bad it would die while driving when I let off the throttle. Was fun when making a turn with no power steering and brakes. The warrantied  one has been flawless over a year now. 

Interesting... so, to add to my confusion, I was in a spot today while troubleshooting where it would not stay started for more than 30 seconds to a minute and just die... so I thought, now's my chance and started removing everything I could... no change until I removed the alternator and ran on battery, so even though all indications point to good, I think it's bad when it heats up. I'm going to verify tomorrow at peak heat again and throw the new alt back in there to see. It's rare to see an intermittent failure like that with an alternator though... but fingers crossed.

[Mopar1973Man]

16 hours ago, wh82 said:

P0122 voltage low recently plaguing me so did the set screw adjust and recalibrate...

 

Make sure to do it right... If not set right it will be on the wrong mode of IVS (Idle Validation Switch). I highly suggest getting a Timbo's there is NO VOLTAGE ADJUSTMENT. It all done by bellcrank angle being there is no electronics in a Timbos APPS.

 

Inside a Timvbos APPS as you can see there is no electronics to foul up the signal.

 

As you can see in the stock APPS it requires electronics to monitor APPS voltage to toggle the IVS switch for the ECM. These are known for issues and electronics failures. 

[wh82]

7 hours ago, Mopar1973Man said:

 

Make sure to do it right... If not set right it will be on the wrong mode of IVS (Idle Validation Switch). I highly suggest getting a Timbo's there is NO VOLTAGE ADJUSTMENT. It all done by bellcrank angle being there is no electronics in a Timbos APPS.

 

Inside a Timvbos APPS as you can see there is no electronics to foul up the signal.

 

As you can see in the stock APPS it requires electronics to monitor APPS voltage to toggle the IVS switch for the ECM. These are known for issues and electronics failures. 

I ordered a timbo APPS yesterday, unfortunately it won't be in till Friday when I was supposed to be gone, with this truck such is life...

 

been investigating all possible parts with no luck... I called DAP and they suggested if I didn't bleed the injector lines I probably have an air bubble killing the engine... My simple mind can't wrap my head around that one, if it can't build fuel pressure, how could it run at all down the road for 10 or so miles till it warms up? Wouldn't the fuel eventually push it out of the injector??

[Tractorman]

56 minutes ago, wh82 said:

called DAP and they suggested if I didn't bleed the injector lines I probably have an air bubble killing the engine... My simple mind can't wrap my head around that one

 

I think I would disregard DAP's suggestion.  If it was the case, the engine would not be able to be restarted without bleeding the injector lines since the starter cranks the engine at a much lower speed than idle.  Also, anytime it is necessary to bleed the injectors (such as after replacing a VP44), only two or three lines are cracked.  Nobody bleeds the remaining lines - they self-bleed while the engine idles.

 

- John

[wh82]

5 minutes ago, Tractorman said:

 

I think I would disregard DAP's suggestion.  If it was the case, the engine would not be able to be restarted without bleeding the injector lines since the starter cranks the engine at a much lower speed than idle.  Also, anytime it is necessary to bleed the injectors (such as after replacing a VP44), only two or three lines are cracked.  Nobody bleeds the remaining lines - they self-bleed while the engine idles.

 

- John

Also while replacing the injectors I just moved the lines enough to the side to get the connector tubes out I didn't take the entire line sets off disconnecting from the VP like I saw in several YouTube videos

[dripley]

2 hours ago, wh82 said:

Also while replacing the injectors I just moved the lines enough to the side to get the connector tubes out I didn't take the entire line sets off disconnecting from the VP like I saw in several YouTube videos

I have done what you have done before but did remove some of the blue phenolic clamps to allow for some wiggle room. As long as you did not have to pry the lines out of the way to remove the tubes you should be ok. In the 4 times I have removed the VP l have only removed 3 lines and never all 6. Injector sezp pretty much the same thing. If those lines are not sealed you know it pretty quick.

[Mopar1973Man]

Taught you well being you just told my secret. 

[wil440]

Boy am I glad I got a mechanical lift pump, engine turns voila fuel pressure.... nowt controlled by DODGEy electrics other than the command to start, I'd P pump my truck tomorrow if I could get the parts to do it and throw the auto in the skip and convert to manual and bin the body and convert to 1st gen.... oh  I need a 1st gen OR fix my 3500(rust) which BTW is not diesel and has never ever let me down....