I've got a AEM wideband gauge hooked up to the Test Pipe bung.
Ever since I've installed it new a few months ago, I noticed that there is about a 1 to 2 second delay in response; so the readings are not exactly realtime. It's always moving around a little bit, but if I accelerate, it will wait a second or so, then jump on the rich side, same thing with deceleration, there is a delay.
It doesn't seem normal to me, I'm wondering if it's defective or needs to be calibrated? Should I have had a bung welded on the downpipe instead? it's just a few inches further back, so I didn't think it would make a difference when I installed it.
I searched, couldn't find anything on this delay issue.

Anyone else experience this?

 

mine does the same thing and it's installed on the downpipe.. idk... maybe it's just the wideband. i've never thought about calibrating it.. maybe someone else can chime in

 

I have the AEM UEGO with the wideband O2 in the test pipe as well. I don't really look at the gauge much, but I know that the logged A/F values match up exactly with throttle position and load. The gauge may have a slight delay, but it's usually used to give a general idea of the A/F ratio; it's pretty difficult to focus on the gauge and drive at the same time.

 

im pretty sure they are all delayed a bit
mine is, my cousins is, my friends is
just the way it is
and the difference between dp to test pipe shouldnt make a diff, mines in my dp

 

if you put the wide band in your test then what do you do with the sensor??

 

yep, it lags just a weee bit the innovative wideband units reportedly have faster response than the AEM units. I had one but it gave me lots of trouble and i got tired of screwing with it.

 

I paid about 220 for the aem wideband, and I was expecting better response. oh well.

the o2 sensor from the cat is in the catback bung with the non-fouler. never got a CEL.

 

$220 for a wideband is pretty damn cheap, especially considering how much they were only a few years ago. During my DSM days, I had to log timing advance and monitor EGTs in order to tune with an SAFC; now I can use a wideband and tactrix cable for all my tuning needs, all for around $300.

 

mine is fine i have my bung welded in the 1 o'clock position on the DP at about where the double hanger is and the wideband reads fine no delay

 

you have two bung on your exhaust?

 

Yes, the Megan exhaust comes with a bung on the testpipe and a bung in the catback (probably so it fits evo 8's too).

 

Yeah, I think they all delay a bit. First you must think about it a little bit though. The air has to flow from your engine through your exhaust to the sensor. This process takes a bit because of the velocity. I think the gauge is probably more accurate at a higher load because of the increased exhaust gas flow and volume.

Maybe I'm wrong, but I think I'm right, or at least close.

 

There is something to it, but not seconds... Even at idle the air moves from the engine to the end of the exhaust in less than 2 seconds I'd say... Guessing again - that would mean that it shouldn't teak even half a second to reach the wideband at idle. UEGO has more delay than that. (Yes I have one too) One more thing I hate about the AEM wideband is the log speed... If I'm trying to make an accurate log and log only the few necessary things (2byteload,rpm,airflow,timingadv,tps,AFR) in Evoscan, the UEGO is so slow that you get 3 values copy pasted together because it's not reading fast enough. On the other hand from what I've seen - the Innovate unit can keep up with fast logging and is more responsive. My next wideband is def. an innovate lc-1.