Fuel Trims dont change
01-12-2005, 10:01 AM
#1
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Fuel Trims dont change
What would make my fuel trims not change? They are at 0% and don't change. I'm geussing either bad o2 sensor or crappy programming but I know somebody running same programming I there fuel trims are changing. How can I test my o2 sensor?
01-12-2005, 06:28 PM
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Well if the 02 is bad then the ecu has no way of knowing how much fuel trim to change.
Just log the 02 readings with the vag and you should be able to see if they are working correctly or not.
01-12-2005, 07:55 PM
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I watched them while I was idling and they were changing
but how fast should they change at idle? the primary was all over the place but I don't have the secondary plugged in so I don't even remember what that was doing but I dont think it matters. If the 02 sensor was out of wack but still giving values would the ecu ignore it and just keep the values set at 0? I'll have to check tomorrow what the values look like while on the gas. Also would the back 02 sensor work in the front? probably not but I cant remember what the connectors look like. Thanks for the help, haven't gotten many replies on this topic and I posted it everywhere! Looks like I finally stumped so ppl 