XFI How can you tell the WB is going out?

[Razor]

having issue where my readings at idle change.. one day it reads 13.8, another day it reads 15.7 without changes to the VE table.

Is there a test like cross counts on a narrow band? Or another issue which could skew the readings?

 

[Eticket]

Razor,

When your WB02 is reading the high number, is it moving at all? i'm having a similar issue that mine seems to be just fine 1/2 the time and the other 1/2 of the time, the O2 is high - like it's not there.

I've contacted the FAST tech guy - he's thinking it's an O2 or wiring.

John

 

[V6RACER]

Did you check timing and fuel corrections in different temp ranges??

ie Maybe you have some corrections that are kicking in at difference ATS, CTS levels.

 

[Razor]

Razor,

When your WB02 is reading the high number, is it moving at all? i'm having a similar issue that mine seems to be just fine 1/2 the time and the other 1/2 of the time, the O2 is high - like it's not there.

I've contacted the FAST tech guy - he's thinking it's an O2 or wiring.

John

Yup.. like i'll be cruising and get to a light..then I feel the engine hesitating and the WB says 15.7.. crack the throttle it goes down to 13.0.. drive it around get to a light it says 13.8-14.0 same fuel pressure, same coolant temp, same TPS, etc. I'm going to disable my wideband and drive it around see how it responds..

 

[DR BOOST]

to check if the wide band is working correctly, look on the main dash and read the UEGOS AND UEGOR numbers.

i forgot what they should be but the help section in the xfi i believe states it.

 

[SloGN]

check to see if the map kpa is changing . i had a similar problem and the 5 volt wire was changing enough to make the output change and thus the ecm made corrections thinking the kpa changed when it did not.

 

[BADDGUY6]

Yup.. like i'll be cruising and get to a light..then I feel the engine hesitating and the WB says 15.7.. crack the throttle it goes down to 13.0.. drive it around get to a light it says 13.8-14.0 same fuel pressure, same coolant temp, same TPS, etc. I'm going to disable my wideband and drive it around see how it responds..

Mine does the same thing with the AC on. My charge in the AC is a little low so the compressor cycles on & off at idle. When it cycles on at idle the motor stumbles and the AF goes to 15xx. had to raise the VE idle cells 5 points up to idle at 13-14 when the compressor kicks on. (Runs a little rich with AC off) And start closed loop at 1250 rpm.

 

[Eticket]

I think mine is actually a different issue. Mine seems to change on its own - cracking the throttle doesn't seem to make a difference. Hard to tell because the fast box was on someone else's car, so I hadn't had enough time to try to diagnose.

Razor, are you sure you don't have your close loop parameters set right? sounds like it's going into closed loop when you crack the throttle (as it should) and just needs some fine tuning on the open loop idle? Not knowing anything else.. it seems like you're then meeting your RPM threshold for closed loop and that's what it's doing.

This is what I got from Fast tech support:

Go into your dashboard set-up and add UEGO(V), UEGOS (R), AND UEGOS (S). Disconnect the o2 sensor and turn the ecu on, and look at these values. It should be V=3.51, S=1.02, R=4.98. If that is ok, the ecu is just fine, either the 02, or its harness may be at fault.