7890A/5975C GCMS Pressure Issues

Hi everyone,

In running FAME samples on a DB23 column, I keep getting an error message of "Neither GC nor MS collected, consult logbook". This started with a one time error message of "Front Septum Purge Shutdown", but  it has not popped up since I was first having issues. The logbook gives the error message "Front inlet pressure not ready Run Time 0.20" with every current test run that I do. My injections seem to go fine and my system eventually reaches the correct pressures, but in monitoring the actual vs. setpoint log, I can see that my instrumental pressure is lagging behind the setpoint by about 0.015psi as it climbs in my method. I am running in splitless mode with a full gas tank and max pressure of ~20psi so I am unclear where my issues are coming from and why the pressure incline is so slow. In terms of troubleshooting, here is what I have done so far:

1) Leak tests for inlet/tank/added PTFE tape around joints that may be leaking

2) replaced the front inlet septum, gold/washer, checked the liner (old but barely gets used, <10 samples per month), trimmed the column for clogs 

3) Tuned the MS, run basically every diagnostic test in the service mode and they all came back fine

4) Tried running with and without gas saver on, both had the same issue

Any ideas on what could be an issue/what my next step should be? Thank you!!

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