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o2 sensor

  1. Focus ST Discussions
    How hard is it, (if possible at all) to replace the bank 1 sensor 1 mainstream o2 sensor on the Focus st? Really don't feel like removing the downpipes to take the o2 sensor off and don't really have the time to.
  2. Focus ST Discussions
    so i recently had a crackle pop tune, i took it off after running it for a week. I don’t have a catless downpipe and i took the time off 2 weeks ago. The other day i had a check engine light pop up so i scanned the code. it was for the o2 sensor bank 1. My ST doesn’t backfire anymore like...
  3. Focus ST Discussions
    check engine light popped up last night. I ran a crackle pop tune for a week then i took it off a couple weeks ago and went back to normal (no tune). should i be worried or can i drive on this to work?
  4. Focus ST Purchasing
    Which o2 defouler actually works and fits with the downpipe so I don’t have fitment issues on my ‘17 fost.