HELP!! bad alternator or APPS??

[ruedger455]

Today i went out and popped my hood to check the oil and noticed my drivers side negative battery cable was unhooked like it came loose. I thought i fixed my apps when i reset it but i must have just forgot to put the negative cable back on the battery. So is my rapid studdering a bad APPS? or is it a bad alternator? I do have the p0122 code and it cleared while the cable was unhooked.  I dont wanna replace one and have it be the other. But while the negative cable was unhooked i didnt have any issue with my shuddering. Im kinda stuck until i figure this out.cause i cant drive over 50mph without it shuddering like crazy. Any help would be greatly appreciated.

Thanks, kimber

[dripley]

Can you explain shuddering a little better? Engine skipping, cutting out, vibrating or the like. How are you reading the codes? Little more info on the truck you are driving would help also. I myself have been dealing with some apps issues but the only thing I have happening is some surging of the rpm. Still very driveable.

Welcome.

[ruedger455]

Its like the converter wont lock and its locking and unlocking.  I know the alternator can do this but with the 0122 code which is the apps,  Not showing up when the battery cable was unhooked it had me thinking it could be either of them. It only does it at 45mph and 55+mph it does it whether the od is on or off and with cruise control on or off.

[Mopar1973Man]

Lock and unlock is the alternator. I would pull the alternator have have it tested for AC noise.

The P0122 is just a lo volt code for the APPS sensor. Typically this would make for a dead pedal more so than cycling the torque converter.

[dripley]

You can pull the fuse on the alternator and see if that helps. It will just run on battery power then and take the alternator out of the equation.

[ruedger455]

Yea i know that code usually goes hand in hand with dead pedal but so far my pedal is good.  But ill pop the alternator out i guess and get her tested.  I was hoping my alternator was ok cause they are a bit pricey lol 

[Mopar1973Man]

Be aware...

My alternator test GOOD. Now the crazy part the rear bearing was good but the rear housing was damaged allowing the alternator shaft to bounce. This in turn ate the brushes quick on one. Then it turn created a weak connection on the slip rings. Still pass the test bench though.

Another way is to use a AC voltmeter that can measure small voltage like 0.01 to 0.1 AC Volts. Basically start the truck and with all your loads you can turn on. Now measure at the BATT post of the alternator red lead and your black lead just touch to either the alternator case or the passenger side NEG post. Best to test on the alternator case though.

0.01 to 0.03 is about normal.

0.05 is marginal. Might get away without problems or might be random.

0.1 AC volts and greater is a fail.

[ruedger455]

Ok thank you,  so i can test it withouttaking it all out.  Im gonna do that first,  what are the chances this is my issue?  From all the posts of other people that have the same issues its the alternator.  If it is the alternator whats my best bet for a new one?  Should i get one woth higher amps?  With my airdog 150 im nlt sure of i should get a higher output or not. 

[dripley]

The higher out put alternator want hurt your AD, High or low voltage is bad on it. 

[CSM]

Another thing to check out is all the connections to and from the alternator.  Up there in the rust belt especially.  Check the field wire and the feed wire from the alternator that routes from the alternator post to the fuse/junction box on the drivers fender.  Corrosion or a bad ground can make for intermittent high resistance and noise as well.  I am a big fan of dielectric grease on connectors!  

And by check, I mean pull them and wire brush the connecting surfaces off if they aren't shiny.  

Edited December 10, 2015 by CSM

[ruedger455]

So i should just get a oem replacement?

[Mopar1973Man]

What ever you do for replacement have the new one tested. I've seen both Bosch and ND alternators brand new in the box FAIL without ever making it to the vehicle.

[ruedger455]

Alright ill have the new one tested before i take it.  Thanks for the help guys,  this is my first cummins.  Had it for a week and it started having these problems.  

[ruedger455]

Would this be a good replacement?

 

 

http://m.oreillyauto.com/mt/www.oreillyauto.com/site/c/detail/USL1/13874N/01468.oap?year=2001&make=Dodge&model=Ram%2B2500&vi=1400061&ck=Search_01468_1400061_4983&pt=01468&ppt=C0330&un_jtt_v_thumb=4

[Buzzinhalfdozen]

I have that alternator. The first one lasted about 6 months and 5k miles and just quit charging one day. The second one has about 15k miles on it and I've noticed the AC voltage is starting to climb on it. Not in the danger zone yet but any higher and it'll go back for a warranty. 

[ruedger455]

Ok so thats a negative lol i want one that gonna last.  But i dont want one of those grean weenie ones lol

[Me78569]

Call a local alternator shop, I am sure there is one if you live in a largish town.   Have them rebuild your code with good parts.

[dripley]

While the alternator is most likely your problem it never hurts to test the old one or at least unplug the fuse and see if the problem goes away. Hate to see you spend the money and find out it is something else.  

[ruedger455]

Ok i went out to start my truck it fires up then dies almost immediately.  I dont get it? Now it will crank but not fire.

Edited December 10, 2015 by ruedger455

[dripley]

Do you have a way to check for trouble codes? They will help narrow down the issue,