Hello,
I'm using HP 1100 autosampler. There is a fine teflon tube called waste tube coming out from the injection valve. This is connected in waste holder in the leak tray. We use red PTFE vial septas from agilent and we have small septa pieces coming out from this waste tube. I also have an ghost peak on my chromatogram? Anybody seen this before? Is it a faulty needle or inappropriate septa? How to clean up the injector?

Are you generally making more than one injection per vial? Typically making numerious injections from the same septa will cause a coring affect. In most cases, selection of the right septa for the number of injections planned will take care of this problem. You may also wish to use a septa that is already pre-slit. This of course depends on the amount of organic within the vial. You don't want it to evaporate quickly.

We have also seen Teflon from the septum break up into the vial. In our case, it made it to the injection valve and we had to take it apart to clean out the fragments. We have since changed vial suppliers and have not had any problems since. As far as the ghost peak, we have also seen this from vials where multiple injections are made. However, we have only seen it when TFA had to be added to the sample preparation.

Thank you both!

I have a test solution on my system suitability and I inject it 6 times from the same vial. Otherwise I make max 2 injections from the same vial. I'll have to consider changing my vial supplier. Ghost peak did not came from the septum. It was traced back to dated tetrahydrofuran in one of my mobile phases.