Step  | Action  | Value(s)  | Yes  | No  | 
|---|---|---|---|---|
1  | Check for any kinked exhaust pipes. Are there any kinked exhaust pipes?  | --  | ||
2  | Repair or replace the exhaust pipe(s) as necessary. Is there still excessive back pressure?  | --  | System OK  | |
3  | Remove the muffler and visually check for restrictions. Are there any restrictions in the muffler?  | --  | ||
4  | Replace the muffler. Refer to Muffler . Is there still excessive back pressure?  | --  | System OK  | |
5  | Check for a crimped tail pipe or an obstruction in the tail pipe. Is the tail pipe crimped or obstructed?  | --  | ||
6  | Remove the obstruction or straighten the crimp in the tail pipe. If the tail pipe is damaged, replace the muffler/tail pipe assembly. Refer to Tail Pipe . Is the exhaust system still restricted?  | --  | System OK  | |
7  | Check for a plugged three way catalytic converter. Is there a plugged three way catalytic converter?  | --  | --  | |
8  | Refer to Restricted Exhaust System Check in Engine Controls to diagnose the cause of the restriction. Is the exhaust system still restricted?  | --  | --  | System OK  |