innovative idle air fuel ratio problem

[gotsomegetsome]

mods: Cometic MHG, reconditioned/resurfaced head + valve job, air/water intercooler setup with new aluminum pipes, vent to atmosphere bov, open air exhaust (straight pipes basically)

electronics to go with this setup: innovative lc-1 + gauge, apexi SAFC2 + random gauges like egt, boost, etc

problem: when i start up the car and let it warm up, i get a consistent 20.1 afr with the wideband set to gasoline and everything. I started the wideband in open air to initiate the o2 sensor and then ran it in exhaust gas just cruising around the neighborhood.

How big of a problem is this? Has anyone else encountered this problem before? What can i do to fix it, etc.


ive taken the o2 probe out of the exhaust and exposed it to free air, did the recalibration, and then put it back it to make sure. checked codes on the unit, im stumped

 

[gotsomegetsome]

nada?

 

[grimreaper]

what does the exhaust sound like? pops and gurgles?

You put the sensor before the cat correct? any exhaust leaks upstream?

Does it show a richer af ratio at cruise?

 

[gotsomegetsome]

what does the exhaust sound like? pops and gurgles?

You put the sensor before the cat correct? any exhaust leaks upstream?

Does it show a richer af ratio at cruise?

I dont have a cat and no there are no exhaust leaks before that
it does not pop or gurgle because i have the safc set at 0% correction
the only time it pops is when i let off the gas and the bov lets out air to the atmosphere

when i am cruising the afr starts to climb like 15, 16, 17 +
when i put the engine under load or add gas it goes down to 11, 12 etc

 

[grimreaper]

What do your vf's read at idle when its displaying this?

Boost leak test? condition of injectors and their o rings? Fuel pressure?

 

[gotsomegetsome]

What do your vf's read at idle when its displaying this?

Boost leak test? condition of injectors and their o rings? Fuel pressure?

vf's?

no boost leak. i spent months on that prior to this and to my best understanding that would cause bad idle, and my idle is just fine about 600rpms give or take

injectors, fine. o-rings, new. did all that when I replaced hg and did valve job. fuel pressure, i would assume it to be okay. havnt touched it at all. only changes to fuel system is the deletion of the fuel dampener with the driftmotion kit. I have no way of testing fuel pressure as of this point, and also that should affect the way the car drives, no noticable differences when driving at all

 

[grimreaper]

Assuming because the car drives fine that everything is correct is not how i would go about it. Start at the basics, plugs, wires, timing and go forward
The tsrm has a nice checklist of things to go through for a lean idle (and most other issues). Why not start there?

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=19


Are you 100% the free air calibration was done properly?

 

[gotsomegetsome]

Assuming because the car drives fine that everything is correct is not how i would go about it. Start at the basics, plugs, wires, timing and go forward
The tsrm has a nice checklist of things to go through for a lean idle (and most other issues). Why not start there?

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=19


Are you 100% the free air calibration was done properly?

ok let me reiterate this...i replaced the head gasket, during this time in order to make sure everything was good and right, I have checked timing wires, new plugs, new timing belt, pulleys alligned, cps good, 10 degrees before tdc, compression in check, and everything else ive told you before.

back to my question, which is not about my engine or anything in my engine.
relating to the free air calibration, I started the unit in outside free air, then restarted it in the exhaust (before any cat which i dont have) and ran the engine. I am fooled because I am getting readings of 20.0 0.2+/- and that is basically like air which is impossible on the exhaust side. there is no leak in the exhaust. there would have to be a considerable leak to where I would not only notice the leak very quickly from looking at the exhaust, but also listening to the exhaust.

perhaps the module is set to the wrong fuel type? I dont know because I am unable to hook up the computer connection to a laptop
maybe its the sensor that came already broken?

I am also using the wideband o2 in place of the stock o2. how does this affect the situation, or does it at all?

 

[grimreaper]

Next time lay all your cards on the table. You did NOT say you did any testing. You threw bits and pieces of what has been done to the car in over a few posts.

Is the wideband sending an o2 signal to the ecu? or is the stock one just unplugged?

so the gauge has to be adjusted with a laptop and you havent gotten around to that step yet? If your work (gauge setup) isnt complete how is there really an issue?

 

[CajunKenny]

What did your instructions say about your wb sensor location?

I just installed an AEM and the instructions stated that the sensor had to be mounted 18" MINIMUM downstream from either the turbo or manifold. You're running the LC-1 so it may be different; but, I doubt it will vary all that much. I think your wb sensor needs to be mounted further downstream.

Not sure how that would impact the afr's; but, I would double check the LC-1 instructions.

 

[dbsupra90]

What did your instructions say about your wb sensor location?

I just installed an AEM and the instructions stated that the sensor had to be mounted 18" MINIMUM downstream from either the turbo or manifold. You're running the LC-1 so it may be different; but, I doubt it will vary all that much. I think your wb sensor needs to be mounted further downstream.

Not sure how that would impact the afr's; but, I would double check the LC-1 instructions.

that is for extended life, it wont effect the a/f.

you need to hook it up to the laptop. mine went a little crazy one time and it was because it somehow went to a custom fuel setting.

 

[gotsomegetsome]

okay i'll try the laptop thing. i mounted it about 6 or so inches from the turbo id say. now the custom fuel setting....is that just like a hiked up afr graph, like everything is +# from the correct afr? i'll check the books to see as well

reaper: obviously the o2 sensor has been replaced with the wideband. the engine would not run if it wasnt. i wouldnt be getting down the street for crap.

 

[jetjock]

Obviously? No wonder you're having problems...

 

[gotsomegetsome]

well i mean how else would the engine run? if i am correct, and i am pretty sure i am correct, the engine does not run very well at all if the 02 sensor is not hooked up. I said i had replaced the o2 with the wideband, so by process of elimination.....

sorry for assuming..

 

[jdub]

The motor will run just fine without the O2...gas mileage and emissions on the other hand...

 

[suprafanatic]

my O2 sensor came unplugged once and i didn't know it, i was driving down the interstate and my AFR's were in the 13s instead of upper 14's low 15s. So the car will run, it'll just be richer. As for my wideband, it reads lean at idle to, i usally get a reading around 17 or so. You mainly need to be worried what it says when your making boost.

 

[gotsomegetsome]

thats weird because my engine really will not run if the o2 sensor is not hooked in....maybe thats also combined with my iscv which is dirty which i need to clean now that i think about it


well i have to get that thing hooked up to my computer then....does anyone know if a usb conversion will work? i dont have a serial port on my laptop but plenty of usb ports

 

[MA70_Powa]

I have an innovate LC-1 too but I haven't installed it yet.
By what you've said here does that mean you keep the stock o2 sensor and stick the wideband in as well? I thought you plugged the wideband into the stock plug on the harness? I'm confused. sorry for the mini hijack.

oh, and fyi my car ran fine-ish without an o2 sensor too - but it was super rich.

 

[jetjock]

The O2 sensor has the least authority of any on the engine. That doesn't apply to only this car either, it's EFI 101. As was already pointed out the ECU will default to running the engine slightly rich with a disconnected or shorted lambda input. The behavior is mandated by federal emissions regulations and any engine that doesn't do it has other problems.

MA70: With a WB you have two choices: 1) Leave the NB connected or 2) Use the WB's emulated NB signal if it has one. Because the NB is more accurate I recommend doing the first...

 

[MA70_Powa]

Ok sweet, thanks for that

/end mini hijack