1. Welcome to PlowSite. Notice a fresh look and new features? It’s now easier to share photos and videos, find popular topics fast, and enjoy expanded user profiles. If you have any questions, click HELP at the top or bottom of any page, or send an email to help@plowsite.com. We welcome your feedback.

    Dismiss Notice

1999 2500 6.0L-started as just an alternator...

Discussion in 'Chevy Trucks' started by JTVLandscaping, Jan 22, 2014.

  1. JTVLandscaping

    JTVLandscaping Senior Member
    Messages: 860

    Looking for help, replaced the alternator last week. over the weekend I noticed the lights were flickering and the volt gauge needle was bouncing a bit. It leveled out and only did it a few times until tonight. Got home, took the alternator out and brought it to Napa. Tested fine. The battery tested low, but without charging it they couldn't load test the battery. So even though it was a new alternator that tested fine, I've had that before and it turned out to be bad. Luckily, I originally replaced it because it was doing funny things while plowing so I wanted to be proactive, and I never even returned it for the core yet and knew it still worked. Swapped it out but may have messed something up. Now the truck runs horribly, seemingly wanting to stall. The only thing I can come up with is I had to take off the air intake hose to get at the tensioner and maybe I cracked it or something...afterall it's only 2 degrees out. Obviously tomorrow I'm gonna dive into it and check it for a vac leak but just wondering anyone has any advice regarding what else it could be. Thanks
     
  2. myzx6

    myzx6 Member
    Messages: 90

    Did you plug the mass air sensor back in?
     
  3. JTVLandscaping

    JTVLandscaping Senior Member
    Messages: 860

    Funny you should ask...this morning when it was running horribly, I UNPLUGGED the MAF, it now runs great. :confused::confused:
     
  4. kimber750

    kimber750 PlowSite Veteran
    Messages: 3,673

    Normally a sign of bad MAF. But that should throw a code.
     
  5. Whiffyspark

    Whiffyspark 2000 Club Member
    from SOMD
    Messages: 2,402

    Get battery tested
     
  6. mn-bob

    mn-bob Senior Member
    Messages: 132

    Did you get the truck fixed ? if so let us know what you came up with, the plug on the side of the alternator have been known to have bad connections try bending the prongs in the plug together a bit and re-install with dielectric grease. Clean and tighten the battery cables too.
    Hope this helps


    Buck
     
  7. JTVLandscaping

    JTVLandscaping Senior Member
    Messages: 860

    Put the old alternator back in and it solved the issue. Still have the MAF unplugged which increased the idle and that's been giving me a delayed shift, but it's back together and plowing tonight. Clearly a vacuum or sensor problem that needs to be addressed asap, once I have time between storms. Thanks for the help guys!
     
  8. myzx6

    myzx6 Member
    Messages: 90

    Plug the maf sensor back in then unplu the regulator connector on the alternator, if it runs normal with alternator unplugged then you have a broken or corroded ground wire somewhere. Could very well be the main ground off the battery full of water, salt and corrosion
     
  9. Moose's Mowing

    Moose's Mowing Senior Member
    from SE PA
    Messages: 198

    not to hijack, but the main ground off the battery....where does that run to exactly. My gauge cluster is still on the fritz and that's the last possible thing it could be. It's been too freaking cold to crawl under and search around for it, esp with the bottom of the truck covered in ice and slush. If I could pinpoint it, I might be halfway motivated to go clean it all up. FWIW, my truck is an '04 with a 6.0. I tried following it down under the block once or twice but gave up case it's so miserable outside.
     
  10. dieselss

    dieselss PlowSite Fanatic
    Messages: 10,973

    It's the cluster.
     
  11. Whiffyspark

    Whiffyspark 2000 Club Member
    from SOMD
    Messages: 2,402

    Those clusters always screw up. Known Chevy issue
     
  12. myzx6

    myzx6 Member
    Messages: 90

    Defiantly cluster, we have a guy that rebuilds them with stronger motors for $150
     
  13. Moose's Mowing

    Moose's Mowing Senior Member
    from SE PA
    Messages: 198

    it's not the cluster, been there done that already. I did the ignition switch too. it's gotta be a crappy ground somewhere. The gauges work sometimes for several days, then stop, I also sometimes have a dead battery after the truck sits for a few days. Other times, it'll sit for a week or two and be fine....makes no sense.