What mechanism can cause this?

[SemiAuto]

I made a 50% toluene 50% tetradecane by weight standard, mixed, and got 27% tol and 73% tetradecane by Area% on my 5890 Series II TCD detector!!! I shot the same mixture on a 6890 with same conditions and got 52% toluene and 48% tetradecane by Area% on its TCD (which is what I expected). Has anyone ever seen this type of discrepancy or have any idea what is wrong with the 5890?

Thanx for your time.

[Peter Apps]

My money would be on inlet discrimination.

Peter