View Single Post
Old 03-24-2014, 02:00 PM   #2 (permalink)
Master EcoModder
Join Date: May 2012
Location: Tampa, FL
Posts: 1,554

Volt, gas only - '12 Chevrolet Volt Premium
90 day: 38.02 mpg (US)

Volt, electric only - '12 Chevrolet Volt Premium
90 day: 132.26 mpg (US)

Yukon Denali Hybrid - '12 GMC Yukon Denali Hybrid
90 day: 21.48 mpg (US)
Thanks: 168
Thanked 343 Times in 238 Posts
So the best guess I can give is pre-ignition from the higher air temps. I assume you are using a wai?

Does that car use VVT?

Best software I have had experience with is OBD2007 for data logging. I can only suggest cleaning the throttle body and appropriate sensors/air control valves, as well as check/replace spark plugs. Maybe use a higher octane and observe changes.

  Reply With Quote
The Following User Says Thank You to ksa8907 For This Useful Post:
Cobb (03-24-2014)