Subject: Re: Hmmm, need some troubleshooting help (a little long) Author: skucera : member since July, 2008 : 19 posts Posted on: 2009-10-01 00:45:13

Those errors and the rich exhaust are classic symptoms of old oxygen sensors that need changing. They normally need changing every 60,000 miles or so, sometimes sooner.

Also, look for vacuum leaks. I don't have a V-8, so my advice is generalized, but I've had to track down similar problems on my V-12. I found a split vacuum cap on one of the intake manifolds, and the rubber hoses to my VCV's (Volume Control Valves, for crankcase ventilation) were causing a vacuum leak just downstream from my MAF's on both banks. Life is much better since replacing those hoses, and that little vacuum cap. I also replaced oxygen sensors about 40,000 miles ago, and since my economy is beginning to drop, I can look forward to replacing those next spring sometime.

Also, other causes of vacuum leaks may not seem intuitive. An old oil cap can let air into the crankcase that results in too much of a vacuum drop through the VCV's. A poor sealing gas cap can result in the same problem.

Good luck,
Scott

• Hmmm, need some troubleshooting help (a little long) - geerhed 2009-09-30 21:34:50 (152 views)
  • SOLVED? $8.19 - geerhed 2009-10-26 21:31:48 (4 views)
  • Re: Hmmm, need some troubleshooting help (a little long) - maun 2009-10-15 20:43:34 (14 views)
    • Thanks, Maun - geerhed 2009-10-24 09:10:00 (4 views)
  • Re: Hmmm, need some troubleshooting help (a little long) - maun 2009-10-10 21:52:38 (27 views)
    • OEM - geerhed 2009-10-15 19:17:20 (9 views)
  • Checked MAF, changed O2 Sensors; no change - geerhed 2009-10-08 19:36:32 (60 views)
    • Re: Checked MAF, changed O2 Sensors; no change - paulmer 2009-10-10 00:07:51 (32 views)
  • d2 'CAN message' (what's that?) - rv8flyboy 2009-10-01 10:58:39 (46 views)
    • Re: d2 'CAN message' (what's that?) - geerhed 2009-10-01 11:10:27 (44 views)
  • Re: Hmmm, need some troubleshooting help (a little long) - skucera 2009-10-01 00:45:13 (77 views)
  • Re: Hmmm, need some troubleshooting help (a little long) - paulmer 2009-09-30 23:08:01 (81 views)
    • NOT 'Shogun' Troubleshooting, SHOTGUN Troubleshooting!!! - geerhed 2009-10-01 10:20:52 (55 views)
      • For a moment there, I thought Shotgun troubleshooting was... - bcweir750 2009-10-10 15:13:29 (40 views)
  • make a MAF sensor test - shogun 2009-09-30 22:48:10 (103 views)