P0421 Diagnostic Trouble Code Discussion for April 2005
Warmup Catalyst Efficiency Low (Bank 1)
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| Help Request | Posted | |
| 1998 Hyundai Accent L 1.5L MIL Lamp on VIN: KMHVD14NXW P0421: Warmup Catalyst Efficiency Below Normal (Bank 1). hyundais test is very short--replace converter and/or PCM---not ready to replace pcm yet--any suggestions??? |
April 05, 2005 |
