I hooked up an Auto meter Air/fuel ratio gauge, and about two weeks later my check engine light came on. When the CEL came on the a/f gauge stopped working. I disconnected the Gauge and the CEL doesn’t come back on. My question is the gauge bad, is the wiring bad or the O2 sensor bad, or is it something else. I’ve heard that Auto meter A/f gauges aren’t very good. I have it mounted right under my radio, could this be causing some sort of interference?

 

what code was it reading? if your o2 is bad youll be running rich.

 

It threw a fault on primary O2 sensor. after i disconected the gauge i reset the system the CEL is no longer on, and hasn't come back on.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MinuteRice &raquo;</TD></TR><TR><TD CLASS="quote">I’ve heard that Auto meter A/f gauges aren’t very good.</TD></TR></TABLE>

Then you heard right. Get rid of it, its useless. It'll only tell you if you're above stoich, or below it. Narrowband O2 sensors have a voltage response like a light switch with the trip point being 14.7:1.

 

yeah if you want to have a air/fuel ratio gauge, definately get a wideband o2 sensor system, it'll read what your "actual" ratio is.

And something I've learned in the past few weeks: If you're messing around with wiring then ALWAYS solder your connections! Believe me, it took a week of reseting my ecu over and over until i realized that "pigtailed connections" just arent good enough!