This weekend when I drove to the track my fjo was reading that I was running pig rich. It was a lot colder out this weekend compared to the last few times I have driven the car so it should have been showing I was running leaner instead of rich. I made a few changes on in my ems but I am questioning if the wideband is still acurate. I drive with it installed all the time so is there a way I can tell if it is reading correctly or do you need to recalibrate it after a while?

 

They do need to be calibrated to open air, but not until the sensor gets pretty old.
The change is a/f is most likely due to the colder temps. You may notice you will build a little more boost when its very cold out also.

 

What is you fuel management? I have noticed that with Uberdata and my 800cc injectors my car will run noticably richer when its cooler out. I assume the IAT is overcompensating too much with large injectors. I just make it a point to tune my car on warmer days and dont mind knowing that its running a little richer on cool nights.

 

I am running aem ems. I thought when it was colder out it would make the car run leaner? Is this not correct?

How do I recalibrate it? Just take it out of the exhaust and turn the fjo unit on with the wideband in the fresh air?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by underpressure02 &raquo;</TD></TR><TR><TD CLASS="quote">I am running aem ems. I thought when it was colder out it would make the car run leaner? Is this not correct?

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It would if there was nothing to compensate for temperature changes but almost every efi system has an IAT so the ecu can counter changes at least somewhat. In most cases it might not fully compensate but my setup seems to over compensate.

 

Still did not really get a good answer. Also how do I reclaibrate the unit?

 

i know there are more people running the fjo then just me.