Many Codes from Bucking

[glmoore001]

I have had a problem with the truck bucking severly when you get hard into the throttle. I had mostly blamed it on a leaky sump, but when I last looked, that problem has been solved. The problem was
consistantly bad in cold weather and had all but gone away during summer. That is, until today on our first really cool morning in a while.
It threw lots of codes this time:
P0217 engine overtemp condition
P0230 fuel pump relay control circuit malfunct.
P0234 Engine over boost condition
P1689 no comm betweem ECM and IP
P1693Turbo charge control circuit malf.
Lift pump pressure never dropped, 13-15 psi the whole time it bucked.
RPM never dropped, it held steady at 2000 psi.
Although I have had a similar problem before, no turbo codes were ever included in the list.
I had an engine overtemp one time this summer, if it generated a code when that happened, it never turned on the light and was not cleared so that may be the one listed.
Could this be a PCM, ECM type issue? Maybe losing contact at the connector?
Thanks Gary

 

[BarryG]

Not sure where you got the codes text but don't believe they are all correct at least the 1689 and 1693 the rest of them I think are correct. The 1689 being the one that would relate most to your symptoms. The 1689 is not an oil pressure code but a communication failure code between the ecm and the vp44 injection pump which could certainly explain the bucking. The 1693 code is called a companion code and it means there is another code set within the pcm (the other computer) and really doesn't mean anything in and of itself.
You might try going to the Blue Chip Diesel Website and check out his troubleshooting and diagnostic section it is pretty good info.
https://www.bluechipdiesel.com/
It could be a bad pump but could also be as you mentioned a loose plug or a bad ground somewhere of which there are plenty to check, maybe even a bad battery/ies.

 

[glmoore001]

Crap, I forgot about the screwed up code definitions on some of the websites.
I will have to fix it.
Thank you for the link, I cannot read it properly on my phone, will have to wait till I get home.

 

[KATOOM]

Looks like you're suffering from electrical gremlins due to either corrosion buildup on electrical connections/cables, or bad batteries, or issue with major grounds, or alternator generating too much AC voltage.

 

[glmoore001]

I put in two new Interstate Batteries, bought a battery cable kit and changed every cable on the positive and negative side of both batteries.
I have not taken an AC reading from the alternator. How would I do that?

 

[glmoore001]

Does there happen to be a chart somewhere that shows the locations of all the grounds?

 

[DavidC]

https://mopar1973man.com/topic/13280-ac-ripple-testing/?tab=comments#comment-166492

 

[KATOOM]

Using a basic volt meter which will read in AC as well as DC...

Switch the tester to AC and set to 0.000v. You test by connecting the red positive line of the tester to the alternator output main on the back, and touch the black negative line of the tester to the alternator housing.

Have someone help you by starting the engine and turning on EVERY electrical component, lights, radio, AC, etc... Then ramp the throttle up to 2000 rpm and see what the tester tells you.

 

[glmoore001]

Just to be clear, dont confuse this issue with the torque converter lock / unlock problem. This is an entirely different issue. This is not a change of rpm as it was with the torque converter problem, this is a complete momentary loss of power, RPM never changes in the split second that it happens. I have even begun to wonder if it has something to do with the transmission itself.

 

[DavidC]

It is clear but AC ripple can cause many problems on electronic vehicles

Dave

 

[glmoore001]

It is clear but AC ripple can cause many problems on electronic vehicles

Dave

Ok. I will check it out!
Is there a safe way to clean ECM/PCM type connectors? Will contact cleaner work?
Thanks.

 

[DavidC]

I would disconnect the batteries and let it sit for a while, draining capacitors etc.. Disconnect and spray with contact cleaner (be sure it is plastic safe as there are some out there that will literally destroy plastic), try to coat the pins as best you can with dieelctric grease and re-assemble.

Dave

 

[glmoore001]

I checked the ac voltage on the alternator. Running with all accessories off, I never got above .035 vac. It is a different story with accessories on.
Lights, fan, radio and turn signals.. check again and the meter is bouncing between .070 and .150 vac.
Thanks.. Gary

 

[DavidC]

For future reference do not use flashers/turn signals. Just constant loads. lights, AC, radio etc. The flashers have surges lighting up filaments etc. and could skew readings.

Dave

 

[glmoore001]

Do the readings indicate that I have bad diodes, or should I run the test again without the flashers?

 

[DavidC]

Run again, no flashers or anything cycling if possible

Dave

 

[glmoore001]

Run again, no flashers or anything cycling if possible

Dave

Thanks Dave. Tested again with headlights, radio and fan on high. Ended up with
.066 to .085. VAC.

 

[DavidC]

Sounds like your ok with a no load reading but getting marginal but you are very close at .035, I am not so sure I would worry about it but test frequently to see if that number increases. If you have a Denso moparman1973 sells the pack, Genosgarage may have them or foster truck. Mine is a Bosch. This also depends on how good the meter is also.This is the general consensus.

Originally I post 0.1 VAC would be a fail but under different circumstances, some people were getting issues below that number. So the 0.05 marginal number pops. Basically, if you can test and reach or pass the 0.05 (50 mv AC) I suggest having the alternator bench tested to verify if it bad or not. Because ever truck has different loads during the test and there is no way to accurately load the alternator from test to test so that why I suggest all load off hoping to even out the loads and get a test number we can all play by.



10 to 30 mV (0.01 to 0.03) is a normally good alternator.

50 mV (0.05) is getting marginal bench testing is advised.

100 mV (0.1) is failing. Bench testing is still strongly advised to verify the alternator.

Once you fail both your test and then a bench test you can safely say the alternator diodes are done.

Dave

 

[DavidC]

Gary, you need to fill out your signature for the truck including any mods etc.

Dave

 

[KATOOM]

Thanks Dave. Tested again with headlights, radio and fan on high. Ended up with
.066 to .085. VAC.

Thats too high. Some people will call this "acceptable" but depending on the application and whats going on, this much AC ripple could cause all kinds of problems. Actually some electronics are so sensitive to this that it can be damaging.
Here's a couple of articles you should read to best understand whats happening and why its important not to run an alternator thats contaminating the elctronic field.

https://mopar1973man.com/cummins/ar...ter-issues-and-alternator-noise-testing-r388/

https://mopar1973man.com/cummins/ar...l/alternator-ac-noise-explain-in-detail-r562/