Kia Spectra Accelerating on its own

I drive a 2009 Kia Spectra. Mileage - 89,000. About a year ago, very infrequently, I started noticing that the engine would start racing when I would try to come to a stop. Now, almost every time I start the car, the engine is racing while it is still in park. And when I come to a stop sign or stoplight, the engine races when I put on the brakes. This is NOT an issue with the mat hitting the accelerator. Lately, also, the car is starting to die for no reason when I bring it to a stop. I took this in to a mechanic, they could not find a problem–they cleaned off some cables but the engine was racing when I turned it on to drive home. But reading some sites on the WEB indicate many other KIA owners are having this experience, but KIA dealerships are not helping or admitting anything, and no one seems to have any sort of solution for the problem.

Have others experienced this problem? Does anyone have a solution or suggestions?

I would think about replacing the Idle Air Control Valve. I had a bad one on a Dodge Dakota and it drove like a different truck after I replaced it. It had your Kia’s same symptoms.

Floor mat issue?

IAC valve or related parts.
Try cleaning the air flow sensor too. Can’t hurt.

Years ago my daughter’s Taurus had a high idle issue that was not cured with a new IAC valve and the techs were perplexed.
Then , once, while continuing to inspect for debris, bent lever, kinked cable or other reasons it would get stuck,
we had the intake hose off and were looking down the throat of the throttle body while working it through its paces.
That’s when I noticed how worn out the butterfly plate was on just one side. The spring tension held it over to one side all the time and it wore a crescent slit between the butterfly plate and the throttle body housing…
causing it to never be all the way closed…
causing the constant high idle.

You can not buy a butterfly plate…you have to buy a throttle body.
HAH ! not this penny pincher !
I built one from sheet metal.
Works like new.

A home brew throttle plate? That’s a cool solution @KenGreen . I’m working on a high idle problem on my early 90’s Corolla, just got the new throttle body gasket, so I’ll take the throttle body off the car this weekend probably for a look-see. Hopefully won’t need to home brew a new plate … lol …

High idle can be a perplexing problem. All great comments above. Since this seems to involve braking, the OP should consider too a problem with the brake booster. It’s powered by intake manifold vacuum, and if the booster diaphram leaked air – maybe only when applying the brakes – that could allow extra air flow into the intake manifold which would increase idle speed. It might be possible for a mechanic to temporarily clamp the vacuum source tube as an experiment to prove or disprove this idea.

These are VERY helpful suggestions. At least now I can have some sort of intelligent discussion with my mechanic. Thanks for sharing your expertise and experiences. I hope others will continue to comment with ideas, and I will report back after taking this Kia back to the shop.

Did you say that there are many other Kia Spectra 2009 owners who are experiencing these same issues? What sites did you find these complaints on?
I will need to collect all this information if you would please provide it to me. Last year, on April 20, 2016, my mom, who was driving a Kia Spectra 2009, my husband, and me were driving 3 separate cars on our move down to Las Vegas. There was a fatal car accident in which she was killed, colliding with a truck who was trying to pass a semi. The three of us were driving 70 miles per hour, but when the police checked her vehicle after the crash, her speedometer clocked her at around 85-87 miles per hour, which is impossible. We haven’t been able to figure out what happened, but she lost control of her car for no apparent reason, and it has left us dumbfounded and grief-stricken. When I read about the issues you were having with your gas accelerating automatically, it made sense to me. Any information would be much appreciated. Thank you

Was having the same problem with my 2009 Kia spectra. Turns out it was a Cadillac converter.

Still having the same issue

Was the problem resolved by removing that Cadillac part, and replacing it with the appropriate Kia part? Using parts from a different make of car is rarely a good idea.


Deleted :::::

I doubt that the catalytic converter was the culprit for high idle, especially since you still have the issue. Take your car to a different shop that can evaluate the issue properly.

At first I didn’t realize this was a typo, and I thought this meant DL had tried to convert her Kia to a Cadillac … lol …

I have heard of carbon buildup in a throttle body causing this, not specifically in a Kia Spectra.