Car lose speed then picks back up

I have a 2011 Hyundai Sonata with 50,000 miles on and lately while driving my car would lose it speed and I would take my feet off the gas pedal and press it again and it will speed back up… I took it to Hyundai a couple of times and they keep saying they don’t see anything wrong every time and I keep telling it that it don’t happens every time… but now it’s happening a lot… they cleaned the fuel once but that didn’t work and they say it’s nothing with the transmission or anything else what else could it be that they are over looking

Is it perchance a manual?

If so, your clutch might be slipping. If not, perhaps your best option would be to take follow the “kick it up the ladder” process described in the paperwork that came with the Owners’ Manual. I assume it’s still under warranty. Keep all your copies of the shop orders and attach copies of them to the formal complaints.

Good point. If the clutch is slipping the engine rpm will increase while the vehicle speed decreases.

What conditions do you notice this? Driving on the freeway mostly, 60+ mph? Or at lower speeds?

At first it was at slow speed not its happening more on the freeway

It’s a automatic

At first it was at slow speed not its happening more on the freeway It’s a automatic

It’s a automatic At first it was at slow speed not its happening more on the freeway

If it’s still under warranty, trying to diagnose and repair it yourself will not only cost unnecessarily, but it might even invalidate your warranty for any related problems in the future.

Try the “bump it up the ladder” process I mentioned.

Just as a curiosity, does this have a CVT (Constantly Variable Transmission) or is it a conventional automatic?