Signs and causes of irregular performance and increased fuel consumption in a 2015 Toyota Highlander

Hey, I can well understand your concerns. I had similar problems in my 2018 Toyota RAV4. In my case, it was cables/plugs that were faulty and caused some of the symptoms you describe. The jerking when accelerating, increased fuel consumption and the check engine light coming on sound very similar. It was definitely a serious problem as it affected the performance of my car significantly. The repair mainly consisted of replacing the faulty cables and plugs. I recommend you find a reliable mechanic and have the car checked thoroughly. Cables/plugs could be the problem, but there could be more to it. Good luck with it!

(Translated from German)

Hey, thanks for your input! It's reassuring to know that I'm not alone with my problems. Your experience with the faulty cables/plugs sounds really similar to what I'm going through with my Highlander right now. Can you remember the cost of the repair you had? I want to get an idea of what I might be looking at. And most importantly, have you had any other problems since the repair? I'm really a bit worried if this is just the tip of the iceberg....

(Translated from German)

Hey, yes, I can understand why you're worried. Well, the repair costs for the defective cables and plugs cost me €95 at the time. Fortunately, after the mechanic fixed the problem, I had no further problems with the symptoms mentioned. In particular, the malfunction of the knock sensor, which I had once suspected, no longer appeared. So, at least in my case, it wasn't the tip of the iceberg. Hopefully that will reassure you a little. But be sure to get your car checked out! Good luck with that!

(Translated from German)

Hey, thanks for the quick and detailed reply! It really reassures me a bit to know that your repair was successful and you had no further problems. 95€ sounds like a fair price, I hope I'm that lucky. Thanks for the advice, I will definitely get my car checked thoroughly! Let's hope it's nothing major.... Really thanks again, I really appreciate your help. I better get to the mechanic now. Bye and see you next time!

(Translated from German)