2008 Hyundai Sonata: jerking or lurching

Filed Apr 25, 2025 · Engine, Transmission · VA

Bought in 2023 @ 98k miles. Have had trouble with 1.it would only start in drive, then that seems to have self corrected. 2. In drive, car would not accelerate properly, and would slow as though I was braking, but no foot on brake. Had rear brake sensor replaced, seemed better for a while. 3. Developed oil leak at 120 miles which valvoline characterized as "not serious...just keep checking it and topping it off." So, have been doing that. Today after oil change, it began running rough, lots of vibration, then the shifting problem, sluggishness, and new..smoke from under hood on driver's side. No check engine lights at all. Nothing registered as hot or overheating. Turned off car, checked oil and trans fluid, both in proper range for warm engine. Let car sit and cool for an hour. Decided I had parked too close to the propane tanks for a smoking car, so I decided to start car just to back it into a space across the lot. Car had no issues- No smoke, no jerking or vibration, no sluggishness, no phantom braking. This car has done this same thing about once every 6 months since I've had it. Changed a tire sensor, that seemed to fix it once. Stopped using cruise control altogether, that seemed to help once. My brother is an ASE certified high school auto mechanics teacher who ran his own shop for 20 years and worked on trucks for VDOT for another 7 years and he cannot diagnose it. I know it has something to do with not being in the correct gear, but it's not reliable, and I have a hard time believing it's just my vehicle.

Filed Mar 31, 2019 · Electrical, Engine · 152,800 miles · TX · 1 injury

2008 hyundai sonata 6cyl dohc 3.3l / 152812 water pump went out. Replaced it. Then water ended up in the oil that got into the lifters. Ended up getting another motor. Then my A/C stopped working (didn't blow cool or cold air). Changed oil and oil filter myself along with the oil sensor ( connected to oil filter spot) that was leaking bad as long as the car was running.I was driving on the interstate, in front of a loaded 18 wheeler, driving 75 then my car jerked real hard then dropped down to 40. I had to pull over illegally to keep from getting hit by the truck. As I was catching my breath I turned the car off. When I started it back up it made a weird tick noise. Haven't heard that noise since. When I pulled off it hesitated to change gears from 2 to 3. It finally changed and did not come out of 3rd. Got it towed home. Had my moms boyfriend to check the transmission. He drove it and it was fine. Next morning started car and it sounded like a vacuum cleaner. (low volume) finally it went away. When I headed to work, it hesitated at first. The vacuum noise came back and was louder. Then I sped up to 50, it hard jerked again, and stayed in 3rd gear. As I went further loss power in inside lane of highway and car was smoking under the hood. Like it didn't know I was pushing the gas pedal. Started shaking at around 20 miles an hour. Pulled over and check engine light came on. Called a friend to pull me back home. It was reversing fine but would not go forward. So I changed the accelerator pedal sensor (whole pedal) that wasn't the problem. So then I changed the entire fuel pump/ injector. Still have all parts by the way. That wasn't the problem either. Put it on the machine and it gave a code for ECM and oxygen sensor. Esc light came on as well as TPMS, when I started the car. I could move forward but it was like I wasn't. This all started in february 2019

Filed Apr 25, 2016 · Electrical, Engine · 108,000 miles · GA

While driving the seat belt light came on. About a minute later the radio shut off. Next most of the dash lights came on , the engine would not make power/accelerate, and the braking seemed weak/jerky. Pulled into a parking lot as soon as I could. Now all dash lights were on/blinking and the radio, sunroof, windows etc would not work. Thinking it was an electrical issue I left it running to investigate. Next thing I know the car is overheating even though the gauge isn't showing it. Steam everywhere and the overflow popped the cap off. Shut the car off. Once the car cooled I was able to see what happened. Oil has been dripping on to the alternator from a leak in the valve cover gasket. This killed the alternator which in turn caused the control/braking/acceleration issues one it was on battery only. I'm assuming the fan was not cooling either which resulted in the overheating.

Filed Jan 9, 2012 · Transmission · 61,500 miles · NY

While stopped at a busy intersection, with engine running and clutch to the floor (disengaged), the car began to lurch against the brake. The clutch began engaging by itself because the concentric slave cylinder had failed at 61,500 miles. The dealer advised the car was 1,500 miles out of warranty, total cost to repair was $1950.00 and 3 days of service. Because the leaking hydraulic fluid "soaked" the clutch, the $794.00 clutch/pressure plate needed replacement as well. Hyundai will not honor any "goodwill" adjustment.

Filed Jun 12, 2010 · Brakes · 35,000 miles · IL

Rear brakes sticking on. First occurred at 35,000 miles and dealer notified me that the brake pads needed replaced, but upon inspection I saw that only one pad was worn to the metal, and the others were at > 50% life. I replaced the pad but the caliper and slider design is defective and the failure happened again at 40,000 miles. This time the car began jerking and suffered loss of brake performance as the indicator, along with noise, smoke, and odor. The hyundai dealer (mike miller in peoria, il) would not fix the problem under warranty, instead saying it was a normal wear item.