Okay, I have a 4 year old AEM EUGO, it's placed 13 inches past the downpipe like 99% of us.
Now, my issue is when I am on throttle my wideband reads PERFECT Air/Feul ratios. In boost, partial throttle, etc. However, if I am at the same RPM for too long my Air/Fuel goes from 14.7 closed loop (with the occasional spikes to 15.1) to about something wacky like 15.8-16.1. However it corrects in a split second.
When I am at idle my ratios are 14.7 for about 1-2 seconds then start climbing til my wideband stops reading (Full lean). A quick blip of the throttle and it will read 14.7 instantly (as if it never actually left closed loop) then start reading correctly as the throttle goes up and comes back down. It will continue to read correctly for about 10-20 seconds then goes crazy again. Sometimes it does not.
I checked for boost leaks and found one of my vac caps came off and I replaced all of them just to play safe with new silicon ones.
I know when a O2 sensor on our buffers at work (Propane) they start reading incorrectly at idle 90% of the time. So I was wondering if this is the same thing?
My reasoning for thinking this is because typically when I pull a bad O2 it takes too long to cool down, but heat up is perfectly fine. I was also wondering if I could do the same bench test where I use a propane torch and multimeter to test voltage while I heat the sensor.
My method at work is to attach to the wires, heat the sensor for no more than a minute and if it reaches .9v it is good, if it takes longer than 3 seconds to get back down to .1 (hopefully .0) then it's bad. I can't find anything on this method of bench testing online for a wideband O2.
*edit* I should have mentioned this, I do know AEM suggests using brake fluid and a rag to test your sensor. However, I am TERRIBLE at wiring and don't want to take my gauge out to test it the way they do in the video. I did think about pulling the sensor through the firewall again and testing it in car, not sure I want the smell of brake fluid in my car though. Anyway, I'd much prefer if my method worked or if there is a way to test it differently to make it work, if at all possible.
Last edited by gusu; 07-05-2012 at 08:00 PM.
Reason: Run-on sentences for great justice!