p0420
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P0420 code problem
I've got an 07 1500 5.7 QC 4x4. She's got roughly 181k miles on her. For about a year now I've had an intermittent cel for P0420. I've done a spark plug change, ran system cleaner, reset ecm, used an infrared thermometer and live data feed to try to diagnose it. Both infared and the LD...- Kurtis West
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- 5.7 check engine emissions exhaust hemi p0420
- Replies: 4
- Forum: Engine & Performance
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*Sighs* P0420 Code after American racing header install with high flow cats
Please forgive me if I’m reposting I couldn’t find a good answer anywhere else I just installed my headers and high flow cats about 3 weeks ago and just got a P0420 code. Has anyone had this issue after a set up like mine? What do you guys think I can do to fix it. Starting to think these...- Samzilla
- Thread
- headers high flow cats p0420
- Replies: 29
- Forum: Engine & Performance
