Service engine light code... Cat gone bad?
#21
TECH Senior Member
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P0420 or P0430? If the cat(s) are bad it'll come right back. No cats or gutted cats you could get 02 sims or have the codes turned off permanently in the PCM. If you just want to reset the PCM/codes without a scanner you can:
Turn key to run, don't start car
Pull PCM BATT and PCM IGN fuses in engine compartment
Wait 5-10 min
Turn ignition off
Rreplace fuses
Warning: Idle speed will be a little grumpy until it relearns, and it'll reset your emissions readiness tests.
Turn key to run, don't start car
Pull PCM BATT and PCM IGN fuses in engine compartment
Wait 5-10 min
Turn ignition off
Rreplace fuses
Warning: Idle speed will be a little grumpy until it relearns, and it'll reset your emissions readiness tests.