Doing some recapping of basic principles and I found my self watching 'week 3 part 1 2014' the video explains about fuel trims, oxygen sensors etc. Now on the page of Paul's book where he is explaining open vs closed loop I noticed that he has listed on times when a vehicle enters open loop 'extended idle'. Could someone explain to me why this would happen, I'd have thought that the system would settle in torder a happy place on its fuel map, what am I missing?
Calling upon my years of experience, I froze at the controls. – Stirling Moss
Turns out it's quite simple, the ecu will enter open loop on idle when the o2 sensors stop working due to not been up to operating temperature. I must admit I don't often come across non-heated o2 sensors at my workshop problem why I didn't think of it straight away
Lesson for the day, don't forget the importance of going back to basics...
Calling upon my years of experience, I froze at the controls. – Stirling Moss
OBD Rick wrote: Turns out it's quite simple, the ecu will enter open loop on idle when the o2 sensors stop working due to not been up to operating temperature. I must admit I don't often come across non-heated o2 sensors at my workshop problem why I didn't think of it straight away
Lesson for the day, don't forget the importance of going back to basics...
Ah yeah, good point! I'm so used to dealing with nothing but heated O2's. Good catch here, sir, don't think I ever put that together before.
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