Base Engine Misfire with Abnormal Valve Train Noise
WARNING: This page is about a different car, the 2020 Buick Regal and 2019 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
| Cause | Correction |
|---|---|
| Worn or loose followers, valve rocker arms The follower, valve rocker arm, and roller bearing should be intact and in the proper position. |
Replace the followers and/or valve rocker arms, as required. |
| Stuck valves Carbon buildup on the valve stem can cause the valve not to close properly. |
Repair or replace the valves as required. |
| Excessively worn or mis-aligned timing chain or chains | Replace the timing chain or chains and sprockets as required. |
| Worn camshaft lobes | Replace the camshaft or camshafts and (Stationary Hydraulic Lash Adjuster) SHLAs (valve lifters). |
| Sticking SHLAs (valve lifters) | Replace the SHLAs as required. |