Someone stole gas from me and now my engine runs weird?

[Dustin Jackson]

Weathers been cooler under 100f and the tahoes been running good. I filled up with e85 today for the first time for fun but I don't think it was needed. Only cost $64 to fill the tank compared to $100ish

Whatever happened I'm not to concerned about anymore just going to drive it until it breaks and fix it again

 

[Dustin Jackson]

Today I took my gas cap off and started the Tahoe to see if it would trip the check engine light and it did not, is that a problem?

 

[Fless]

Why would you expect the CEL to light up?

 

[Foggy]

Sometimes the gas cap being OFF needs to have a full drive cycle to set a CEL..\
It won't happen immediately with the cap off

 

[Doubeleive]

Today I took my gas cap off and started the Tahoe to see if it would trip the check engine light and it did not, is that a problem?

as noted that will not throw a cel right off the batt takes a while