GenVibe - Community for Pontiac Vibe Enthusiasts

Our 2006 Vibe, bought used in Feb, has poor gas mileage, usually getting 23 mpg combined city/hwy. Most we ever got was 26 mpg and that's only been on 2 or 3 fillups.
We've tried most of the suggestions to improve mpg and none has worked.

Has anyone put a different ECM on their car, other than the dealer recall? We were wondering if we could get another ECM and get better mpg. Will we have to have the ECM reflashed or reprogrammed? We've already checked and our ECM had a supposedly "GOOD" number so it is not eliglble for replacement under the recall.

I'm pretty sure several people have given you suggestions on how to deal with your mpg issues. Did you check the front O2? Run a Compression check, inspect the Transmission, the exhaust.
There isn't a AC DELCO PCM for these cars. You need to remember the engine and drive train is Toyota. Now you could find another Denso PCM on e-bay and have it installed by the dealer to correct your issues. There are standalone PCMs but it would run you $1.5K or more for them to be installed and setup.

Bet a dollar to a donut your front O2 sensor has issues.

2X on the compression test. Worn engines often show themselves through overheating problems and low mpg's.

Did you get it reflashed as you said in the other thread?

If so, and no change, I too suspect oxygen sensor first and compression second. Are you burning oil? Manual or auto?