To start with had the car tuned on e85 at boosting performance in Illinois a few months after moved down to Florida after 2 or 3 drives the car started throwing p0171 bank one lean change out the front o2 sensor then got code p0134 bank one inactive. Replaced with the original o2 sensor still getting code p0134. Checked ground check Voltage check both fuse number 8s no vacuum leaks no exhaust leaks no boost leaks. 40 psi on fuel pressure. I'm at a lost. Is there anything I'm missing. Or could it just be as simple at a new tune due to the climate change the car is in.

 

Could it be a bad batch of E85 or that its now winter blend and has more gasoline in it? I also have an E85 map from Boostin and moved to Missouri ha. But still running on a tank of summer E85 as the car does not drive much. Do you have an AFR gauge? Or can you test the fuel?

You may want to call Boostin when you can. I find they are fairly responsive when I need them.