Hi all, dumb-not-really-a-real-car guy here.

I bought a 2011 XC60 last summer, (heard good things about the brand, how reliable they are.) I had been a ford guy prior to this.

I checked the website about fuel and didn’t see a warning about U88 so… to keep it short.

I messed up and ran U88 in my 2011 for about 6 months, before realizing when I bought my 2012 that you are absolutely not supposed to put that in there.

And the check engine light won’t stay out even though, I switched to running it exclusively on 91 again.

The code has something to do with emissions, and I’m kinda hoping to just change out one part and send her down the road. My 2012 has a few more features, and I don’t really need the 2011. (She also has the lovely windshield seal failure, hah!)

I haven’t had much luck finding out what kind of damage the wrong fuel could cause, any ideas for what I should check first?

Sincerely, not-smart-car guy.

 

The check engine light means there is at least one self diagnostic code stored in the ECM or TCM. What codes are stored? Most codes do not go away (and turn the light off) until they are read (then fixed if needed) and erased.

So what should you do first? Scan the car, all of the control units if possible and use that info to make a reasonable, rational diagnostic course of action. You may simply need to read and erase the codes - they might not return, depending on what was the cause.