Results 1 to 7 of 7

Thread: Turbo boost sensor

  1. #1
    Join Date
    Feb 2017
    Location
    Oregon, USA
    Posts
    4

    Default Turbo boost sensor

    Hi guys. First post. Having erratic throttle response. It is most pronounced when it is cold but what is happening is that when I accelerate while driving, it will race up to 2500 rpms then back down to 1400. This cycle will continue to occur all the way 30 minutes to work. I am a decent mechanic but had to take it in to have it scanned after I couldn't figure it out. Threw code p0238. I replaced the turbo boost sensor but it is still occurring. Any ideas?
    2000 Chevy K2500
    6.5 L TD
    256,000 Miles
    Replaced PMD @ 200,000, relocated to front bumper
    Manual Wastegate after vacuum pump quit
    New Lift Pump @ 250,000
    Regular schedule fuel filter replacments

  2. #2
    Join Date
    Oct 2001
    Location
    Granby, Missouri, USA
    Posts
    3,081

    Default

    Sounds like a PMD/FSD issue to me. I've experienced erratic RPM control a few times, and it was always a PMD/FSD problem. If you've replaced that and it still acts up, probably an internal Injection Pump failure.

    Does it happen when using cruise control? If not, it could also be the Accelerator Pedal, but I doubt it.

    Casey
    1995 K1500 Tahoe 2 door, 6.5LTD, 4L80E, NP241, 3.42's, 285/75R16 BFG K02's; 1997 506 block; Kennedy OPS harness, gauges, Quick Heat plugs, and TD-Max chip; Dtech FSD on FSD Cooler; vacuum pump deleted, HX35 turbo, Turbo Master, 3.5" Kennedy exhaust, F code intake; dual t/stats, HO water pump, Champion radiator; Racor fuel filter

  3. #3
    Join Date
    Feb 2017
    Location
    Oregon, USA
    Posts
    4

    Default

    Thanks for the reply. I believed the pmd failure would not have those symptoms. Just a no run condition. I wont rule it out though... It does have the same issues with cruise control on. Pedal checked out ok. Maybe a short in the wiring from the tbs to the pcm? The wiring gets lost in the harness bundle and hard to trace. Anyone know how to test the wiring?
    2000 Chevy K2500
    6.5 L TD
    256,000 Miles
    Replaced PMD @ 200,000, relocated to front bumper
    Manual Wastegate after vacuum pump quit
    New Lift Pump @ 250,000
    Regular schedule fuel filter replacments

  4. #4
    Join Date
    Oct 2001
    Location
    Granby, Missouri, USA
    Posts
    3,081

    Default

    Definitely try the PMD first. Will probably save you a lot of headache.

    When mine has failed, it wouldn't hold a steady RPM, even on cruise control.

    The PMD failing typically results in a stall or no start condition, but can also fail to full throttle scenarios... which is quite scary. Unsteady RPM is also another symptom.

    Casey
    1995 K1500 Tahoe 2 door, 6.5LTD, 4L80E, NP241, 3.42's, 285/75R16 BFG K02's; 1997 506 block; Kennedy OPS harness, gauges, Quick Heat plugs, and TD-Max chip; Dtech FSD on FSD Cooler; vacuum pump deleted, HX35 turbo, Turbo Master, 3.5" Kennedy exhaust, F code intake; dual t/stats, HO water pump, Champion radiator; Racor fuel filter

  5. #5
    Join Date
    Feb 2017
    Location
    Oregon, USA
    Posts
    4

    Default

    Okay you talked me into it! I suppose for whatever reason it wasn't the fix I'd still have a spare. Thanks.
    2000 Chevy K2500
    6.5 L TD
    256,000 Miles
    Replaced PMD @ 200,000, relocated to front bumper
    Manual Wastegate after vacuum pump quit
    New Lift Pump @ 250,000
    Regular schedule fuel filter replacments

  6. #6
    Join Date
    Feb 2017
    Location
    Oregon, USA
    Posts
    4

    Default

    Nope! The PMD was not it. Now I am thinking It may be the wiring between the sensor and the ecm. Thoughts anybody?
    2000 Chevy K2500
    6.5 L TD
    256,000 Miles
    Replaced PMD @ 200,000, relocated to front bumper
    Manual Wastegate after vacuum pump quit
    New Lift Pump @ 250,000
    Regular schedule fuel filter replacments

  7. #7
    Join Date
    Jan 2006
    Location
    Boissevain, MB., Canada
    Posts
    187

    Default

    Check all vacumn hoses attached to sensors and turbo.
    '95 GMC K2500, "Bullet"Ex. cab short.4X4, 377,000kl on truck, 177,000kl on AMG engine, auto. 3:73 Ltd. slip, FSD remote mount, OPS relay,AFE air IN, Kennedy 3 1/2" OUT . '83 F250 HD3/4 " Robert The Red Ford"4x4 460, 3:55'posi . 2005 GMC : G WHIZ" crew short box, 5.3, 4:10. , '88 Bronco II 4X4, '95 141,000kl Ford F150 EX. short box, '92 "Toy" 4 runner 273000kl ,'63 Mercury 45000miles !!!! Auto insurance co. is my mistress !!!

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •