Car stalls wot won’t restart

Discussion in 'Mazdaspeed 3 Troubleshooting' started by Caleb Englert, Dec 10, 2023.

Watchers:
3 users.
  1. Caleb Englert

    Caleb Englert Greenie N00B Member

    Joined:
    Dec 9, 2023
    Posts:
    5
    Trophy Points:
    3
    Location:
    Missouri
    Ratings:
    +3 / -0
    I have a 2012 gen2 speed, mods- Cobb high flow downpipe, Cobb intake, auto tech HPFP, ets top mount intercooler, turbo smart 50/50, Cobb accessport freektuned 93.

    Recently having an issue at wot car will shut down and hpfp act is reading 2073psi, checked wiring was all good to pressure sensor, replaced sensor and no change. Also car won’t restart when it’s showing 2073psi if you crack the pressure sensor loose let some pressure off car will start right up and drive normal unless you go wot, just needing some insight on this or if someone else has had this issue haven’t found anything online, also have no codes either.
     
    Caleb Englert, via an iPhone, Dec 10, 2023
    #1
  2. SyntheticAtmosphere

    SyntheticAtmosphere You only get ONE ride, ONE ticket, ONE time! Silver Member

    Joined:
    Aug 1, 2016
    Posts:
    572
    Trophy Points:
    93
    Location:
    Canada
    Ratings:
    +619 / -0
    <<This>> will help you understand how the system works. In the fuel rail there is a return line with a built in relief valve, called a Pressure Relief Valve. It may be failing. Usually they fail and cause a low pressure condition, however if they opposite occurred pressure would build. If you purchase a new one I would suggest an OEM unit.
    I am not sure if doing a PRV test would help as it usually is for lack of adequate pressure but perhaps a test might show an anomaly.

    <<BigSHO's PRV test>> He has a custom PRV that has a higher breaking pressure.
    How long have the HPFP internals been installed? If they have been in service for quite some time, perhaps a cleaning and rebuild would be valuable. Pay attention to cleaning the Spill valve when you are in there.
     
    • Like Like x 2
  3. Caleb Englert

    Caleb Englert Greenie N00B Member

    Joined:
    Dec 9, 2023
    Posts:
    5
    Trophy Points:
    3
    Location:
    Missouri
    Ratings:
    +3 / -0
    I went ahead and ordered a new prv valve from mazda so we will see if that fixes my issue, the pressure spike only happens at wot you can ease into it and have normal pressure but as soon as you go WOT pressure spikes to 2073psi and car stalls out and wont restart unless you relief the pressure off the rail, also the first time it happened after sitting overnight it would start right back up.
     
  4. Enki

    Enki Motorhead Platinum Member

    Joined:
    Feb 10, 2016
    Posts:
    2,301
    Trophy Points:
    113
    Location:
    Tucson
    Ratings:
    +3,310 / -3
    Aftermarket 2100 PRV installed or it's stuck stuck. Injectors might not be able to open.
     
    • Like Like x 1
  5. Caleb Englert

    Caleb Englert Greenie N00B Member

    Joined:
    Dec 9, 2023
    Posts:
    5
    Trophy Points:
    3
    Location:
    Missouri
    Ratings:
    +3 / -0
    Prv looks to be original new prv comes in Thursday hopefully fixes my issue. i was thinking the higher pressure wasn't allowing the injectors to open because if you'd crack the fuel pressure sensor loose and let pressure out of the fuel rail some it will start right up.
     
  6. Enki

    Enki Motorhead Platinum Member

    Joined:
    Feb 10, 2016
    Posts:
    2,301
    Trophy Points:
    113
    Location:
    Tucson
    Ratings:
    +3,310 / -3
    All the modded PRVs look like OEM.

    Edit: They basically *ARE* OEM, but with a stiffer spring.
     
    • Like Like x 1
  7. Caleb Englert

    Caleb Englert Greenie N00B Member

    Joined:
    Dec 9, 2023
    Posts:
    5
    Trophy Points:
    3
    Location:
    Missouri
    Ratings:
    +3 / -0
    Is a modified prv needed for my setup with the auto tech hpfp or will an oem one be okay?
     
  8. Enki

    Enki Motorhead Platinum Member

    Joined:
    Feb 10, 2016
    Posts:
    2,301
    Trophy Points:
    113
    Location:
    Tucson
    Ratings:
    +3,310 / -3
    No, it's something people do because reasons.
     
    • Like Like x 1
  9. Caleb Englert

    Caleb Englert Greenie N00B Member

    Joined:
    Dec 9, 2023
    Posts:
    5
    Trophy Points:
    3
    Location:
    Missouri
    Ratings:
    +3 / -0
    Replaced the prv and car is back to normal now.
     
    Caleb Englert, via an iPhone, Dec 13, 2023
    #9
    • Like Like x 3
Loading...

Share This Page

Users Viewing Thread (Users: 0, Guests: 0)