Prototype_xB

When i had my car tuned the metering device that's set up with the dyno read out 11.0 across the rpm band. Now, even with such, i noticed the UEGO in the cabin was reading 10.0, which is the richest that it will read, when still on the dyno. I asked the guy tuning my car and he didn't really give me an answer. Since then the temp has dropped some and i noticed now when i get on it WOT the UEGO reads 10.0, 10.2, 10.5. So my question is, could the metering piece of equipment that was used to dyno my car be off? Would the UEGO be more accurate? I'm just worried it's still tuned way too rich.

soros151

AEM UEGO is suppose to be +-.1 accurate.

DK01

I think any one of the devices can be off. The only real way to check is probably use a different wideband and compare the readings.

When you dyno tuned your car, did they use a sniffer at the end of the pipe to read the afr's? The distance between the two sensors can make some difference I would think. But I don't know how much of a difference tho.

318_tC

my uego has ALWAYS read different then the dyno. somtimes up to .4 and ____. I heard UEGO is junk, of course i bought the uego and then heard that. Bastards

yamaha16bw

Dont most dyno's just lay a wideband sensor in the rear of the exhaust for dyno testing? I would think have a sensor welding in 24 inches after the turbo would be more accurate.

318_tC

^never seen it done that way

Guru

Uego is pretty accurate. It does read a tad richer than my dyno wideband but not that far off. I'd say you can probably lean it out a bit so that the AEM reads close to 10.8:1 and your dyno will probably read 11.5-11.6:1. As long as there is no detonation you should have no problems.

zer0

The UEGO probably needs calibrated. But I have also heard that the tailpipe o2 sensors that dynos use, are off by 1.0, its worse if you have a cat... thats what ive heard, I cant back that up though.

PLX FTW!

Butane

iirc you cannot calibrate the sensor on the UEGO, that is why it is crap. My friends supercharged SRT-8 engine said adios, when his uego read richer 1-1.5. so he thought he was at 11.8...when he was close to 13 yikes!!!!

krdshrk

I think it depends on where the O2 is. On dynos, the A/F reading is taken from the exhaust tip.

IMO (and not from a technical standpoint,), atmospheric interference could be affecting it. It may read lower than what the A/F reads...

pollup

i use zeitronix and it seems to be fairly accurate. im at 14 to 15 at idle and roughly 12.2 at WOT.. No problems at all so far. mind you that 12.2 is at 60mph in 4th gear stomping it. in 3rd it drops down to as rich as 9 to 1 so im running very rich.

tikbhoy

hmm, bummer i should have stuck buying the plx instead. ill have to read the aem manual about calibration

rhythmnsmoke

there is no problems with our UGEO..

paul_dezod

The AEM UEGO have been noted to be not the most accurate sensors of all. We have noticed up to a .7 AFR variation when on the dyno.

The common belief is that the sensor is what is the AEM's downside. AEM uses a LSU4.2 which is a cheaper Bosch sensor than the LSU4.

So, with that being said, I have an AEM in my car, so does several others as well............ :shrug:

soros151

Can u change the LSU4.2 TO THE LSU4?

jwaggz82

iTrader: (1)

correct - most places will put the o2 sensor in the exhaust. Honestly - if you have the air/fuel and know about what you are running its going to help you to know about what you are running. Get a narrowband and think about how much worse that will be.

soros151

Yep, I have seen it in the exhaust area.