I am troubleshooting our GC-FID and have a problem. When we inject a 1uL sample, we do not see any sample peaks at the detector including the solvent. I have leak checked the inlet and found no leak. Also, I have replace the inlet liner, septa and gold seal with same result. I remove the column from the inlet and injected the sample directly into the column and placed the column back in the inlet. The peaks are then present at the detector. I am wondering if anyone else has had this problem. I think maybe the electronic component that controls the valve for split/splitless valve is bad? Thanks for your help.