Hi, I’m Ron and I can help you.
I have been in this business since 1975 and also teach automotive repair. I am confident we can resolve your problem together. Please understand that I don't know your skill level. I can't see, smell, hear, or touch the vehicle either, so it may take a few replies to get to satisfactory results. Please be patient!
I also try to give all of the information you may need, expecting a "positive rating" in return. I will also continue assisting you after you have rated me, if necessary. If there is any reason I cannot get a positive rating, please let me know why "in advance", so I can go another direction for you. I am sorry you’re having this problem; I’ll help you through it.
If there were a fault in the computer system, a code would be set, so the best thing left to do is to scan the computer and watch the fuel trims for STFT and LTFT. These readings come from the O2 sensors and will be accurate or a code will be set.
Also be sure to check for any possible exhaust restrictions and any unneeded weight you may be hauling.