AEM AEM wideband readings

[gorf]

My AEM uego has been installed for a while. It seemed to work until I rebuilt my engine. Now when the engine goes to open loop, I read 10 but no lower. If I adjust my safc leaner, I can make the knock count go up, if I richen it, the knock goes away. BUT the aem open loop reading is always 10 and never changes regardless of which way I set my safc. At first I thought it was the safc not working, but because I can make the knock count go away, I now think the AEM is reading bad.

Is there anyway to verify the wideband readings?
Anyone seen a similar problem?

 

[TuRBoTaLooN]

Where is your W/B sensor located? Perhaps it is too far away from the engine and not getting accurate readings. It is also important that the sensor is angled down into the exhaust pipe at like a 30-45 degree angle.

The AEM W/Bs should not need to be calibrated...in fact I don't even know if you can?

Also, it's possible that the sensor is bad. Does it read 14.7 at idle?

 

[talontd92tsi]

sounds like you need a new sensor

 

[viperlp01]

When those sensors go "bad" they ussually read high.... I would say that is it unplugged or not plugged in enough... Moneys on the connection

 

[gorf]

Thanks for the feedback.

Bung is located after flex section and before high flow cat. Bung is angled down probably about 10 degrees. The wideband reads about 15 at idle and does fluctuate with acceleration. The only issue seems to be at open loop full throttle where it always reads 10 regardless of how much I pull or add with the safc.

I'll check the connections, but "I think" they are good.

How often do sensors go bad, or how long do they last?

I know I burn a little oil at start up, I think from a bad valve stem seal. My number one plug shows signs of oil if I start the car, shut it off and look at the plug.

Will oil burning cause the sensor to go bad quicker?

 

[gorf]

Just an update, this was mentioned in another thread also.


One of those DUUUHH moments.

The 10 that I was reading, is the lowest that the AEM wideband wideband will go. Which means I was probably running richer than 10:1.

after solving my richness problem, the wideband now reads normal....

 

[97gst_spyder]

Lol, well atleast you fixed your issue!

 

[vicore]

what is the normal fluctuation in idle?

 

[Turboturd]

usually 14.0-15.5, the car is trying to hit 14.7 and cycles around that number at idle

 

[vicore]

Thx!
Is such fluctuation apparent in open loop while cruising as well? Closed loop is active above 140°C (so never) but still it is fluctuating :-(

 

[curt-s]

In open loop, it does not fluctuate because it ignores the O2 sensor altogether and goes off the MAS sensor and the fuel maps. It's not chasing stoich, it's trying to achieve the ratio defined in the cell(s).

I'm also fairly certain there is no ceiling limit to coolant temperature to switch into closed loop/learning mode, just a floor limit to switch into open loop.