Rented a Durametric for a week WHAT SHOULD I CHECK?

[blue62]

Ideally you have a very good handle on how OBDII (and all the various sensors) work.
Things like short and long term fuel trims.
Pre and post cat o2 sensor function.
What a good pre cat o2 sensor signal looks like.
What a good post cat signal looks like.
What bad signals look like.
Camshaft deviation
What to look for at start up.
What to look for while doing a road test.
How to do a volumetric efficiency test.
The more you know about how OBDII works.
The more info you can pull from diagnostic equipment like the Durametric.

If you have limited knowledge????
I believe you can data log with the Durametric.
Or you could take screen shots of all your readings under various driving conditions.
Then you could study up on how OBDII works. look at your saved data and learn what the data is telling you about the condition of your car.
The Durametric or even a simple OBDII scanner can tell a lot about the running condition of your car.
The better you understand how OBDII and all the sensors work the more a OBDII scanner can tell you.