My 2019 Elantra Limited will do a shudder that you can feel in your seat while idling. It’s only 2 months old, it’s been doing it for a little over a month and wanted to see if anyone had ideas or experienced this and it’s “normal.”
The car has to have warmed up first for about 5-10 mins. It started a month ago at a stop light, it felt like someone very gently bumped into my car because I felt a shudder, and it felt like it was coming from the back, because the back/base of my seat is where I could feel the shudder most. I literally checked once to see if someone had gently bumped into me. They hadn’t.
Then while idling in a parking lot playing a game (Pokemon Go), the car would suddenly shudder intermittently. A couple times it was a VERY strong shudder, but it doesn’t do that much now, it does a shudder that feels like when you shut the engine off when it’s “still in a cycle” or for whatever reason it shudders sometimes when you turn the engine off.
Took it to dealership, waited, mechanic came out to feel it, I said it might take awhile, and it did do it once after about 5 mins, but he wasn’t paying attention and didn’t feel it. So without being able to show them it on demand they can’t do anything or pay attention enough to notice.
Been watching the RPM, after warmed up (5-10 mins) it idles a little below 750. But then it’ll do a very small dip, then recover, it can bobble up and down a few times and nothing happens, but then it’ll do a bigger dip of probably about 100-200 RPM, and THAT’S when the car shudders and then the RPMs recover to their normal position.
I played around to try to get this to be repeatable, and if I use something that draws electricity I can force it to drop RPMs while idling and shudder. AC is off. Have HVAC on auto usually, but if I’m idling and crank the fan speed, the RPMs dip 100 or so, the car shudders and then recovers back to normal idle RPMs. Sometimes it won’t do it immediately, so I just turn the fan up, turn it down, turn it up, and the RPMs start fluctuating and after doing it about 3 times, RPMs do the larger drop and car shudders.
If I’m at a stop for a bit, when I take my foot off the brake, the RPMs also drop ~75-100 and the car shudders. This is less noticeable since usually you hit the accelerator quickly, and pressing the gas seems to cut the shudder short.
All the shudders are quick, image a human shuddering from chills. That’s basically what the car does. But it does it so frequently while idling it’s worrisome.
Anyone experienced this, or have any ideas?