Riffraff Diesel Technical Knowledge Center
Why Your 4R100 O/D Light Is Flashing: Common Codes, Symptoms, Causes, and Fixes
Mar 25th 2026
If the O/D OFF light on your shifter is flashing, your truck is not just asking for attention. It is telling you the PCM saw a transmission-related fault. A solid light usually means overdrive was man
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The “Non-Serviceable HPOP Plug” - Step By Step How To
Mar 11th 2026
If the non-serviceable plug at the bottom of your HPOP is leaking, the factory short-thread plug has likely stripped the threads in the aluminum housing.
This long-thread replacement plug is made from
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OBS 7.3 to Super Duty UVCH Mod: Better connections, better operation
Mar 4th 2026
If your OBS 7.3 (’94.5–’97) has random misses, contribution codes, rough cold starts, or the classic “it runs better when I wiggle the valve cover plug”… you&rsquo
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The Ford “Switch Fire” Recall Family: 99V-124, 05S28 (05V-017), 07V-078, 07V-336, and 09V-399
Posted by Adam Blattenberg on Feb 20th 2026
If you’ve ever heard an old Ford guy say “check that cruise control switch before it checks your garage for smoke detectors,” this is what they’re talking about.
Easilly the mo
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7.3L Powerstroke ICP and IPR Diagnosis/Testing/Set-Up with AutoEnginuity
Feb 18th 2026
Troubleshooting Injection Control Pressure (ICP) or Injection Pressure Regulator (IPR) issues can be done with AutoEnginuity (Ford Enhanced) quickly.
AutoEnginuity can be found here: https://www.riffr
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