P0421 Diagnostic Trouble Code Discussion for December 2012
Warmup Catalyst Efficiency Low (Bank 1)
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| Help Request | Posted | |
| 2001 Hyundai XG300 3.0L No Start VIN: KMHFU45D71 P0421: cat warm up. Hello all;winding down to the holiday and this shows up on a hook! Never saw one of these before;suspected timing belt as cause for no start;pulled cam belt covers to verify timing marks ok.Tested compression;marginal on front bank;70 to 100;cylinders washed? ... |
December 20, 2012 |
