E85 and check engine light

[Brett Hartwig]

Just FYI-

I had a check engine light come last week, no change in performance so I waited until this week to get it checked out since I was getting an oil change anyway. Dealership said Ford has suggested that one possible reason for this light (second time it has come on) may be when a person fills a partial tank with E85. Suggested if you want to use E85 and you currently have gasoline in the tank, wait until you are below 1/4 tank to put that E85 in. They have found that if a person has, hypothetically, 3/4 tank of gasoline and tops off with E85, the engine may not adjust accordingly. The dealership thought Ford would probably be coming out with more info soon so they could pass it on.

 

[Tom Schindler]

Isn't the engine supposed to be able to detect what percentage of Ethenol in the tank and adjust accordingly.



Sounds like the dealer is grasping for straws because they are unable to find some type of problem.





Tom

 

[Todd Z]

Any idea what the numerical code was????



It is possible about the partial stuff, But as Tom said, the computer should adjust..

Todd Z

 

[Richard L]

Yep, I agree with Tom. The FlexFuel engine is designed to accept any mix or blend or gasoline/alcohol, from pure gasoline to 85% ethynol alcohol with no adjustments necessary.



The engine is supposed to have an octane sensor that can adjust to ECU operating parameters based on what fuel the sensor detects. Perhaps your sensor has failed, I would be interested in knowing what OBD error code you are getting with the check engine light??



...Rich