Sporadic loss of ability to accelerate

[rileyh1278]

I have an 06.5 Optima, bought in February. With less than 3,000 miles, a month or so ago, it started having a problem. At first, I thought the engine was dying or stalling while I was driving, but soon realized that it was in fact not stalling. It was just as if I had taken my foot off the gas pedal when I had not. The check engine light comes on, and the gas pedal becomes unresponsive.

I've had it in the shop 4 times since then. The first three times they tried to repair it by tightening up a connection to the TPS sensor, then they adjusted the connection at the computer, then they replaced the TPS sensor all together. The fourth time, they're claiming that they can't find anything wrong with it, and the computer made no record of the problem or even that the CEL came on.

I started a case with Kia's Consumer Assistance number, and they elevated it to the regional consumer assistance rep who just told me today that if they can't reproduce it, there's nothing they can do with it.

Now that doesn't make sense to me. I don't know much about repairing new cars, but I do know how to repair computers. I don't have to see the error to fix it. I know by what the customer tells me what the possible causes are and can troubleshoot them.

Since the computer is telling them that nothing's wrong, they're just shrugging their shoulders. They've taken it on a few drives to reproduce the problem, but it's sporadic and intermittent, so you never know when it's going to happen. And I'm anticipating they're going to hand it back to me and tell me it's fine.

I guess I just have to keep a video camera in the car with me and start it up when the problem presents itself, unless anyone has any suggestions for me?

Thanks!
Riley

[SpectraMan]

Riley:

How often does this happen? Is it at least happening once a week?

I wonder if the KIA dealer has one of the monitoring devices that can be hooked into your car that records what's going on with the onboard computer at the time of an "event", like your accleration loss.

I know that Ford dealers have such a gizmo. Be sure to ask them if they have anything like that, and how long can you keep it.

Be sure to report back what you find out.

Good luck!

-SM

[rileyh1278]

It seems to be happening once a week, sometimes more often, but atleast every Saturday I've had it for the last month or so.

I don't know about the monitoring device, at least that they can leave hooked up. I know they have one that reads the codes, but they haven't offered to leave it hooked up.

It's been in the shop for the 5th time now.

I've been keeping a record of the whole thing at The Optima Problem. If you're interested, check it out for lots more detail.

[N106FM]

I purchased a device on the internet called a Scan Gauge II.
It plugs into the jack under the dash on the drivers side. It monitors a and will display any error codes in the computer.
I leave mine connected all the time as it provide other information as you drive, such as MPG, MPH, Water Temp, Gallons left in the tank, and more. I have a 2006.5 Optima, and this provides the information that the cars trip computer should have.

Mike

[Foots]

I had a similar problem with mine. It would only happen right after start up and its only happened a couple of times, but its been a few months since the last time.

[pista]

could it be a problem with your traction control?
on slippery roads, mine does the exact same thing you describe ie; depressing the throttle increases engine speed unless you hit a slippery spot. then the engine won't accept the signal to deliver fuel even if you give it full throttle.
but by design, it is supposed to do this.
perhaps one or more of your sensors is sending a false signal to the computer and it "thinks" your tires are spinning so it counteracts that by chopping the throttle.
it probably wouldn't show up by throwing a code because it technically wouldn't be a malfunction the computer recognizes as a fault.
just a guess...