1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

1996 F Superduty Won't Stay in Third Gear

Discussion in '7.3L Powerstroke Diesels' started by Jeremy Barnhart, Sep 15, 2020.

  1. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    So this just started the other day on my way home from the market, my truck drover there just fine but when I started for home it acted like it's in limp mode and has a hard time shifting up passed 2nd and when it does make it into 3rd2nd it drops right back into 2nd when I even barely hit the accelerator. Also the transmission has only 500 miles on a rebuild but it's passed the warranty because of time. And there's no codes. Anyone out there have any ideas why this would be happening?
     
  2. DaveBen

    DaveBen Supporting Member Supporting Member

    Age:
    71
    Posts:
    1,644
    Likes Received:
    395
    Joined:
    Sep 29, 2010
    Location:
    Ukiah, Ca
    A little more details would help a lot. What year and model? What model of tranny do you have? Two wheel drive or four wheel drive? I see you live kinda near to Ukiah. I am not a mechanic, just an old fart passing ideas along.
     
  3. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    It's a 1996 F450 or F-Superduty, 4x4, and it has the E4OD transmission. It has about 87,000 miles on it and it looks like it's spent most of those at slow speed because it has 27,000 hours on it.
     
    DaveBen likes this.
  4. DaveBen

    DaveBen Supporting Member Supporting Member

    Age:
    71
    Posts:
    1,644
    Likes Received:
    395
    Joined:
    Sep 29, 2010
    Location:
    Ukiah, Ca
    You might add this information to your signature by going to the Black Line above and clicking your user name and selecting 'signature'. You can add a photo to your User Name.
     
  5. 79jasper

    79jasper Chickenhawk

    Age:
    27
    Posts:
    17,141
    Likes Received:
    1,768
    Joined:
    Oct 13, 2012
    Location:
    Collinsville, Oklahoma
    You will have to do some diagnosing.
    With having no codes (scan it anyways) I will give a few starting points.
    Clean the ebp tube and sensor.
    Look into the map sensor readings.
    Also look at tps readings.

    Sent from my SM-N960U using Tapatalk
     
  6. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    I cleaned the sensor last weekend. What should I look for as far as readings for the map and tps? I’m a new owner as far as powerstrokes are concerned, I have no experience working on them.


    Sent from my iPhone using Tapatalk
     
  7. 79jasper

    79jasper Chickenhawk

    Age:
    27
    Posts:
    17,141
    Likes Received:
    1,768
    Joined:
    Oct 13, 2012
    Location:
    Collinsville, Oklahoma
    Tps should have smooth voltage increase.
    Map sensor is the boost reading. Same thing there.

    Sent from my SM-N960U using Tapatalk
     
  8. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    Do I check the map with the engine running?


    Sent from my iPhone using Tapatalk
     
  9. 79jasper

    79jasper Chickenhawk

    Age:
    27
    Posts:
    17,141
    Likes Received:
    1,768
    Joined:
    Oct 13, 2012
    Location:
    Collinsville, Oklahoma
    You can check both, running/driving, and key on engine off.

    Sent from my SM-N960U using Tapatalk
     
    Jeremy Barnhart likes this.
  10. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    Thank you. I will try this when I get home tonight. One other question is about the cat, it looks like it's the original. Would that all of the sudden clog up and cause the truck to go into limp mode?
     
  11. 79jasper

    79jasper Chickenhawk

    Age:
    27
    Posts:
    17,141
    Likes Received:
    1,768
    Joined:
    Oct 13, 2012
    Location:
    Collinsville, Oklahoma
    The engine doesn't have a limp mode. It can shut down one whole bank of injectors though. Just not the typical limp mode like a gas engine.
    Gut/delete the cat.
    Sent from my SM-N960U using Tapatalk
     
  12. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    I'll take the cat off tonight then too and see how she runs.
     
  13. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    I took the cat off and it still looks good I guess. I can still see all the way through it like a heavy screen door. I ran out of time to test the sensors. I’ll have to do it tomorrow.


    Sent from my iPhone using Tapatalk
     
  14. 79jasper

    79jasper Chickenhawk

    Age:
    27
    Posts:
    17,141
    Likes Received:
    1,768
    Joined:
    Oct 13, 2012
    Location:
    Collinsville, Oklahoma
    What are you using to read data?

    Sent from my SM-N960U using Tapatalk
     
  15. Jeremy Barnhart

    Jeremy Barnhart Registered User

    Posts:
    15
    Likes Received:
    1
    Joined:
    Sep 15, 2020
    Location:
    Lower Lake, California
    I'm using the ELM327 OBD2 Scanner USB Scan Tool FORScan OBD2 Adapter with FORScan. It only came up with P0603, which I was told by a mechanic is there because I changed out the batteries.
     

Share This Page