Check engine light came on in my Yukon need help

I used a Fuel Injector cleaner on my Yukon and now I have codes and a misfire and was wondering what to do

So what engine, what year, how many miles on it, what fuel injector cleaner did you use? And why? Was it missing before the injector cleaner?

You have a 25% Long term fuel trim on bank 1… but short term is zero… Huh?

Were your O2 sensors throwing codes before you did this??

Answer each question and we’ll try and help.

It’s a 2001 GMC Yukon with a 5.3 L and roughly 186300 miles on it and no codes and I used wynns fuel injector cleaners do 0 codes before I just wanted to add it

And I thought it threw the code short term so cleared codes and drove it to see if it would help

I would guess the injector cleaner melted loose some smudge that ended clogging one or 2 of the bank 1 injectors causing your LTFT to hit 25%.

You may have to replace the injectors on that bank… the drivers side is bank 1. The other codes might go away when that is fixed.

Running more injector cleaner might make it better or might make it worse.

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