Sugar as a Cause of Death?

[350SL4spd]

In looking for a cause of death for the 91 300D 2.5 turbo (that I am performing a post mortum on after the motor seized) and it turns out that the owner had some people that were, let's say, "out to get him" and he has a habit of forgeting to lock his car. So, what I am asking is; what does an engine (diesel in particluar) look like after it has burned sugar? What tests can be performed on the fuel to determine if has a high sugar content?
We are attemting to contact the local PD and see if they have any info and to make it a criminal investigation until we can prove that sugar is not a factor.
Thanks for any info that is available!
-Matt-