Sounds like exhaust could be clogged

 

You may be right I'm going to try to check on that

 

I have a 2018 Elantra Sport that starts and shuts off right away. I've tried replacing spark plugs, coil packs, High press fuel pump, Low press fuel pump assembly with filter and pressure sensor, fuel injectors, fuel rail sensor, and crankshaft pos sensor. I've cleaned the intakes, and walnut shell blasted them. I've checked fuel pressures and O2 sensors and finally took the car to the dealer. The Hyundai dealer has had my car over 2 weeks and cannot find the problem either. The dealer shop verified there is evidence of carbon fouling, and they rechecked all the items I replaced and are now checking the turbocharger and Cat. They also said there was evidence of oil on the filter from reverse airflow.

 

My car has around 92,000 miles on it but ran great until it started stumbling with misfires. Ill let you know if the dealer finds the problem.