I have a 2012 optima SX. Other than having to have the engine replaced I've loved my car. One thing does bug me. I have notice that the lag time between pressing the gas petal to when the power comes on. Some times it comes on quick. Like from a stop. However if moving at speed 30 mph and up it feal like there a delay. I assume the engineers programed in some kind of response curve related to speed, gear, boost or possible even steering angle (just a guess). I would like it to have a direct liner response from petal to throttle body.
I'm wondering if this can be addressed by some kind of tune, throttle body upgrade or other aftermarket part.
I have a 2014 SX, no turbo. I've driven many a car in my day and this is the only car I've ever driven that has such a significant delay in throttle response after I push the pedal. It's one of the only things I don't like about my car. I asked my local Kia dealer about it after I first bought it and the local service manager said these just tend to be like that right from the factory. And offered no fix (I've always done all recommended maintenance, throttle body cleaning, etc). Fast forward a few years and my regular local mechanic who I go to for tires and brakes, etc, (not the dealer) heard me complaining about this too, and he told me he also has the same issue (he happened to have the same car, except his is turbo...so yes, it affects turbo Optimas also). The solution he suggested to me is an aftermarket "throttle controller" that he had purchased, and he recommended specifically the X9 model from this company which he said works to fix the issue:
HIKE IT USA
hikeit.com
I didn't like the white face on the X9 and bought the more expensive XS model but the connector it did not fit my car even though their online selector tool said it would. Should've listened to my mechanic (he also went through this not fitting issue apparently). Swapped it for the cheaper X9 which took some time with shipping back and forth, and finally, the X9 does fit (they credited me the difference in price), and boy did it solve the sluggish throttle response (which is totally different from turbo lag). Although they don't show it in the picture, the X9 model comes with a black face you can stick over the top of the white one if you prefer black (matches my black leather interior better). Now this unit in the "Racing Mode" is entirely too sensitive for my taste and may even be downright dangerous in certain situations (best to turn it off when backing up in a busy parking lot for example). The beast will jump if you barely touch it in this setting. I prefer "Sport" mode which is slightly less aggressive but more than solves the problem. There is also Cruise Mode, Economy Mode, Automatic mode (tries to compensate for all conditions), and OFF (you can disable it so it acts like stock again). This thing is ridiculously simple to install. Just unplug the electronic throttle connector from the top of your gas pedal, put a small box in between (snaps in both ends from what you removed), then connect the interface box (what is pictured) which plugs into the other little box you added above your pedal, position it on your dash, and you're ready to roll... and finally I can pass quick, start fast from pulling out turning from one roadway to another, all without having to keep the pedal mashed to the floor... A responsive car with a competent and even moderately aggressive (but still defensive driver who yields to idiots) is way safer, IMO. But the car has to GO when you want it to GO. Hope this helps you and perhaps others who read this and are bothered by the throttle lag in these Optimas. HikeIT should pay me a commission for referrals, ha ha.
