ECM OR VP ISSUE

[Nicholas91]

Recently bought a 99 Cummins 4wd 5spd, my issue is the truck will get a “dead pedal” while driving. I can cycle the key “fast” or engage an disengage the clutch an regain fueling for 5-10miles and will get the 3 dings an lose the pedal again. From what I see the vp is a reman. I cleaned battery cables and replaced the tps and did a calibration with no fix. The previous owner installed a fass in hopes to fix the issue with no luck also. Truck starts every time no issues. Current codes are: p0216, p0122, p1693, p0222 and also have a code on body: module hardware fault. 

[sooxies]

9 minutes ago, Nicholas91 said:

Recently bought a 99 Cummins 4wd 5spd, my issue is the truck will get a “dead pedal” while driving. I can cycle the key “fast” or engage an disengage the clutch an regain fueling for 5-10miles and will get the 3 dings an lose the pedal again. From what I see the vp is a reman. I cleaned battery cables and replaced the tps and did a calibration with no fix. The previous owner installed a fass in hopes to fix the issue with no luck also. Truck starts every time no issues. Current codes are: p0216, p0122, p1693, p0222 and also have a code on body: module hardware fault. 

Do you have a fuel pressure gauge installed?  If not, now is the time to make an investment in one.  I've just been going through the p0122 code.  Installed a Timbo APPS and code has not come back...for now at least (confident the sensor was toast and was not a ground issue).

Edited June 22, 2018 by sooxies

[Nicholas91]

15 minutes ago, sooxies said:

Do you have a fuel pressure gauge installed?  If not, now is the time to make an investment in one.  I've just been going through the p0122 code.  Installed a Timbo APPS and code has not come back...for now at least (confident the sensor was toast and was not a ground issue).

So you think it’s a fuel pressure issue? It just seems like something electrical is cutting out, but something that requires like a electrical reset. I have 3 known good tps’s an no change in issues with any of them

[Mopar1973Man]

Some quick questions...

 

Q: Does the wait to start come on instantly with the key or does it delay for a few seconds before coming on?

I'm looking for sign of AC noise damage on the ECM. If the wait to start light is lagging then the ECM is brain dead till that light comes on. That is the first instruction after the ECM software boots up.

 

Q: What is your AC noise voltage out of the alternator?

Need to measure the AC voltage output of the BATT terminal of the alternator at idle with all loads turned off. The normal voltage is around 30mV AC. Above 50mV AC things get flaky. Above 100mV AC TQ conv lock up issues and weird behavior can be seen. Typically the result is either VP44 burns up the PSG or the ECM does. 

 

Q: What you mean you get 3 dings and lose the pedal? Any lights on the dash? (Check gages, Check Engine?)

I'm puzzled by this the only thing I know of that trips the central timer chime is the Check Gage light, Low Wash light. As far as I know the Check engine light will not trip the chime.

 

Q: What is your fuel pressure going down the road under load?

This has to do with keeping the PSG on top of the VP44 cool if the pressure falls below 14 PSI the overflow valve shuts and all cooling of the PSG stops. So its possible the PSG is overheating. Funny part, very rarely do you see anyone report seeing the P0168 error code for an overheated VP44.

Edited June 22, 2018 by Mopar1973Man

[Nicholas91]

Wait to start comes on immediately, the mV shows 14.5-24.5 depending where I place the ground side of the meter, the dings I’m assuming is a code being active an yes it does have a check engine light on constantly. Unfortunately I do not have a fuel pressure gauge right now but it acted the same before and after a fass was installed.

[Mopar1973Man]

The next step would be to hit the articles and read up on your error codes and preform the diagnostic work. Lets see if we can clean up some of the codes.

 

 

[JAG1]

See if you can get a hold of the invoice for the VP and get the warranty to go with it if P/O will do that for you. Feul pressure needs to be above 14 all the time to keep the VP going.

[dripley]

The dings are weird. It should not ding just for a code. Mine never has anyway and have seen my share.Even though you have a new FASS, monitoring fuel pressure is important. Low fuel pressure will grind up your VP, probably the reason for the p216 code. No telling how long the previous pump might have been feeding the VP to little pressure. With out a gauge you never know how much pressure you are feeding the VP.

[Dieselfuture]

5 hours ago, Nicholas91 said:

the mV shows 14.5-24.5 depending where I place the ground side of the meter

Not sure if this is right. Make sure to use a good meter, cheap ones will read high in range you're indicating. You should see something like this. 

[Mopar1973Man]

15 hours ago, Nicholas91 said:

p0216, p0122, p1693, p0222

 

 

 

15 hours ago, Nicholas91 said:

also have a code on body: module hardware fault. 

 

No such module. PCM or ECM is the only two modules that will report error codes. We do not get Bxxxx codes. Might be a low grade code scanner this is kind of random to see with cheap code readers. 

[Nicholas91]

So a little more to the issue, when it does go dead peddle I notice it’s not a true “dead” peddle. I still have full rpm range when I pull it out of gear and rev it up but it’s a little slower to rev up like a little loss of power but still revs. I can put it back into gear an that’s where it’ll fuel still just not enough to gain any speed but can almost maintain speed somewhat. Now once i cycle the key then it regains full power to where I can actually gain speed like normal. Sometimes it take 1-3 cycles an it’ll drive normal for 10-15miles but other times it multiple cycles of the key to eventually drive normal.

Also if I’m in gears 1-4 an it does it I can just keep the pedal down for 30sec to 1 min while it’s “dead” pedal and 9/10 it’ll regain power an take off but it will not do that in 5th gear. 

[dripley]

Any blue smoker? I experienced something very similar at 75k miles but had a lot of blue smoke when it would happen. Restart the engine and it go away and sometimes it would take 2 or 3 times. Sometimes it would just come out of it on it's own. Turned out to be the VP. It was replaced under warranty and I did not ask many question about the cause.