Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Cars & Trucks (https://www.askmehelpdesk.com/forumdisplay.php?f=41)
-   -   Hissing noise on powersrtoke7.3 diesel (https://www.askmehelpdesk.com/showthread.php?t=187741)

  • Feb 24, 2008, 12:40 PM
    body guy
    Hissing noise on powersrtoke7.3 diesel
    I have a 1999 7.3 diesel. I start it up when its cold to warm up. It goes on high idle , like it is supposed to, but the exhaust will hiss on and off not smooth and even . It also does it driving down the road it makes the truck jerk or lunge. If it is over 40 or 45 degrees it won't do it . Other than that it is a true work horse and will never own any thing else.
  • Mar 2, 2008, 01:03 PM
    MarkNat
    Where in the exhaust will this noise come from? Will it eventually stop?
  • Mar 3, 2008, 05:26 PM
    body guy
    Hi mark nat you hear it at the tail pipe when your outside the truck ,and you canhear it inside the truck (coming from the engine ) driving down the road.
  • Mar 3, 2008, 05:28 PM
    body guy
    It will stop sometimes and other times it won't
  • Jul 12, 2008, 08:25 PM
    kevbone
    There is an exhaust flap actuator on the front bottom of turbo, this actuator will partly close the flap when cold to keep exhaust in engine to warm it up faster, when ecu sees throttle position the flap is supposed to open letting exhaust flow normal, this is a very common problem on 7.3s, you can either replace this actuator, or you can unplug it, if unplugged there will not be a check engine light and engine actually will still warm up pretty good.

  • All times are GMT -7. The time now is 05:20 AM.