well i got my uego istalled about 3 weeks ago, and it worked great for like 2 weeks, but now somethings wrong with it. it jumps all over the place all the time and when i take off it blanks out most the time. what would cause this? should i contact aem?

 

Check wiring. Most wide-bands have a self-checkout procedure. I know on mine if you disconnect the sensor it reads a specific value. When you remove the sensor from the down-pipe it will give you free air.

I suggest you do the sensor self-check to rule out any wiring related issues.

 

so ur saying to just unplug my o2 sensor and just turn on my power to see what it reads? i did have the gauge powered but not hooked up to the o2 and it was steady at like 14.7.

 

anybody else got some input on this?

 

i need to install my uego.....haha, but its probably the wiring....

 

I'm confused. It sounds like it's working like it should be from what you described. When steady crusing, is it reading between 14.7 - 15.2? Or is it ONE constant #? If it's ONE constant #, then it's not functioning right. If it's bouncing between 14.7-15.2 while driving normal, then it's working like it should.

 

no its like all over the place now like at idle or cruising or wot, it jumps everywhere like from max lean reading to max rich reading its just giving me an led rainbow. it was working correctly for the first couple of weeks though, like it stayed from 14.7 to 15.2 and it would hit like 12's i believe at wot, but its just going from green to red like a rainbow effect.

 

are you letting it warm up really good? Mine jumps all over the place until it fully warmed up.

 

yeah it does it constantly, even after warmup and a half hour drive

 

have you pulled the battery and reset everything?

 

yeah i have, i tried it a couple times

 

how did you tap for power? butt connectors, wire taps, or solder and tape?

 

its tapeed in at my ignition fuse, and all the rest of the connections are soldered and shrink wrapped

 

For all it's worth my wide-band was okay for the first week then it would read all over the place -real jumpy readings. Sent it back to the factory and they found a loose ground path inside the unit -PLX fixed it under warranty. It has worked perfectly since I got it back that was like Sept of last year.

Call AEM tech support to get the read-out values for the self test -take it from there.

Basically folks are telling you that yes the A/F will change but not as much as you describe. On the highway you should be getting real close to 14.7-15.2 and it should be relatively stable...unless you are modulating the throttle a lot. The tC ECU goes into fuel-cut under deceleration with your foot off the gas so when you let off the A/F will go frst to lean and then free-air (A/F > 20:1) This is normal on new EFI cars to save gas and lower emissions. Shortly after the deceleration the ECU will go back to 14.7-15.2 it will vary a little bit and vary a little but generally will stay there most of the time when the ECU is in closed loop. Somewhere between 2500 and 3000 RPM's the ECU will switch over to open-loop and it will use a pre-determined fuel map that matches MAF, IAT, TPS and TACH to determine how much fuel the engine needs (There is no feed-back for the primary oxygen sensor back to the ECU, so A/F should be very stable in open-loop. You should be able to see this very clearly with the wide-band O2 (When it's working properly)...