The ole 559 code

[Smooth]

Just putting feeler out see if anyone has run into this before I start the never ending 2350 Fuel rail Test.

Code 559 - Triggered 9 times over a week period.

Fuel Pressure Leakage Test of course first go to, 30 Sec - 22000 psi at 60 Sec still holding 18K. I have seen much worse

But the oddity is When I start the Leakage Test , The trucks starts building pressure as normal around 15K Psi it bottoms out back 5-6K and basically starts over. It did the same thing 3 consecutive times. But each time after it does that truck builds to near 30K psi and stabilizes as it should.

Before starting the Test I did change the High Pressure Relief Valve

Thought would check for anyone that has had a similar issue in the past before i start in with the never ending Tests.