WenmarOpen by Wenmar Pro

Service bulletins for the 2018 Hyundai Elantra GT

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

117 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

By topic

Only bulletins with component: Engine are shown. Show all

Bulletins, newest first
20-EM-001H(1)2020-03-06. Service bulletin. ENGINE AND ENGINE COOLING. Some 2018-2019MY Elantra (AD) and Elantra GT (PD) 2.0L vehicles may have a weakened weld near where the center muffler is attached to the exhaust pipe. This condition may cause the center exhaust pipe of the muffler to exhibit an exhaust leak and/or exhaust noise. Follow the procedure outlined in this bulletin to replace the center muffler assembly to correct this condition.
19-01-016H-12019-12-16. Service bulletin. ELECTRICAL SYSTEM; ENGINE AND ENGINE COOLING. This bulletin provides information related to an ECM (Engine Control Module) software update for DTC P0128: Coolant Thermostat (Coolant Temp below Thermostat Regulating Temperature) logic revision. There are no drivability symptoms associated with DTC P0128.
Campaign T3T Dea2019-12-16. Service bulletin. ENGINE AND ENGINE COOLING; ELECTRICAL SYSTEM:SOFTWARE. Hyundai has launched a Service Campaign to update the ECM (Engine Control Module) software for DTC P0128: Coolant Thermostat (Coolant Temp below Thermostat Regulating Temperature) logic improvement.
Dealer Best Prac2019-05-20. Service bulletin. ELECTRICAL SYSTEM:SOFTWARE; ENGINE AND ENGINE COOLING. Hyundai has launched a Service Campaign to update the ECM (Engine Control Module) software for DTC P0128: Coolant Thermostat (Coolant Temp below Thermostat Regulating Temperature) logic improvement.
19-01-016H2019-05-20. Service bulletin. ENGINE AND ENGINE COOLING. This bulletin provides information related to an ECM (Engine Control Module) software update for DTC P0128: Coolant Thermostat (Coolant Temp below Thermostat Regulating Temperature) logic revision.
5NP-P4Y7D-082018-08-20. Service bulletin. ENGINE. If you are servicing an applicable vehicle with a ?Check Engine Light on? and one or more of the DTC listed below, follow the repair procedure and replace the input/output speed sensor and oil pressure harness.
5NP-M5G2M-082018-08-20. Service bulletin. ENGINE AND ENGINE COOLING. If you are servicing an applicable vehicle with a complaint of ?Check Engine Light on? and one or more of the DTC listed below, follow the repair procedure and replace the related solenoid and oil pressure harness.
5NP-C5F9C-082018-08-20. Service bulletin. ENGINE AND ENGINE COOLING. If you are servicing an applicable vehicle with a Check Engine light on and one or more of the DTC listed below, follow the repair procedure and replace the oil pressure harness.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.