aem wideband.

Moshman1205

Registered User
i cant seem to find any literature on this but i know but the talon i had i could use the wideband o2 sensor and run a wire from the sensor to the ecu giving the ecu the narrowband signal it needed, is there a way i can do this on the s.c? id so which prong is it? thanks guys. Devin.
 
i cant seem to find any literature on this but i know but the talon i had i could use the wideband o2 sensor and run a wire from the sensor to the ecu giving the ecu the narrowband signal it needed, is there a way i can do this on the s.c? id so which prong is it? thanks guys. Devin.

not sure what you mean. the factory ecu is not programmed to interpret wideband o2 readings. if you want to datalog wideband readings you'll need a moates quarterhorse. I heard a rumor about being able to datalog wideband o2's via the EGR connector. or something to do with the egr. but reguardless that is only when your tuning via xcal or quarterhorse. the factory ecu wont be able to make changes to your AFR that way.

edit: are you trying replace your factory upstream o2 sensor(s) with a wideband so you can monitor AFR and still obtain a narrow band singal for the ecu? I know both sensors work based off of voltage readings. so..I don't know what makes a wideband different than narrow. hmm. I've gotta do some research.
 
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from what I've read in quick google searches, a wideband uses a 5 volt scale whereas a narrowband uses a 0-1 volt scale. that right there eliminates a wideband as a possibility for a factory ecu.

narrowband readings are affected by egt where widebands aren't. widebands use an electrochemical pump where narrowbands do not. they have different metals for sensing and whatnot. etc.. thats pretty much the jist of it.
 
yes, you can send a narrow band signal to the SC to replace the signal it will get from it's existing sensors. Most people do this by splicing the harness that the stock sensors hook to since the stock harness is right where you need to be for your new sensor.

Otherwise you'll need to get the wiring diagram for the EEC for your year car to identify the pin to plug into.
 
thanks mike, that seems to be the most accurate answer so far, but you say splice into and do that. are you saying insert my wideband sensor ino the pre existing hole and run the wires into the stock plug?
 
Something to consider, although some wideband controllers can output a narrow band signal for your computer, from what I've read, the widebands don't react as quickly as a narrow band sensor. This might result in delays in the AFR adjustments the computer is making. This is just speaking generically, and may not apply to the AEM sensor you have and the speed of the EEC in the SC may not be that fast.
 
How quickly a wideband responds is usually related to where in the exhaust stream it is placed. If its farther back it will give a slower responce to current engine afr and will 'blur' the actual afr due to cooling and slowing of the gasses.. Or something like that. I know that my arm wideband was pretty quick and real sensitive to afr fluctuations. It was always bouncing around and hardly ever stayed within .5afr which to me means that it's working. If it stayed at 15.0 at idle I'd be concerned that it wasnt reading properly. Also was consistsnt with dyno widebands. The aem isn't a great wideband gauge, it's mid grade honestly. Its cheap enough for most, but still has a good refresh rate and I personally like the digital display better than autometers gauge.
 
Edit. I get what you meant about the speed of the sensor and the eec. Didn't pick that up the first time reading it. My bad
 
So which wideband sensor is better than an aem one? And the location would be a stock replacement. Which brought me to a.sk the question about the location on the wiring
 
schooling..

Wideband sensors generally do not make good replacements for narrowband o2 sensors because their switching speed from stoic to lean or stoic to rich. This can impact fuel economy as the EEC-IV teaches itself by gradually enriching the fuel until the O2 says too rich, then gradually leaning the fuel until the O2 sensor says too lean. if the sensor takes longer to say too rich or too lean, the longer the engine computer takes to correct things.

So for a daily driver it is better to keep narrow bands in command for the engine computer, and just add a wide band.

That said, if your wide band has an output to simulate a narrow band sensor, then you can splice that into the signal line that normally comes from the narrow band oxygen sensor. for folks using something like the LC1 which puts the sensor electronics closer to the actual sensor, splicing into the O2 sensor harness at the exhaust manifold makes more sense. If your electronics are in the car and the wire comes from there, then it may make more sense to splice in at the EEC-IV plug.
 
the electronics are in the car. and so would be the single wire for the narrow band signal. where in the ecu does it go? and which computer am i going into to do so. which prong i should say.

edit, yes i am aware of how it works and what it does which is why i am trying to figure out where to put the narropw band sensor wire so the car doesnt go retarded. thanks for the "schooling" though.
 
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On an SC Thunderbird, the eec-IV is in the kick panel of the passenger side. The connector on the computer is on the bottom, and if you pull up the carpet and insulation plus the plastic cover you should have access. You'll need to figure out which wires to cut, and splice into. Sorry, no diagrams on my end.
 
thank you mike. thats half the battle. and i dont think im going to start cutting and splicing until i am sure of which one it is lol
 
May I suggest you locate the EVTM (Electrical Vacuum Troubleshooting Manual) for your year SC, and use its diagrams?

Helm Inc has them for $22.50, and you can find them used on eBay for less.

THAT said - you could always put, say, a toner signal on the old HEGO connector and trace it back to the ECM plug (suggest taking the ECM out first, until you're happy with it.) Also tone the same wires back from the other HEGO connector to find the two or three in common ( 12V, Heater ground, Signal ground - only the actual signal isn't shared between the two IIRC. But that's what the EVTM is for!)

RwP
 
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