M3Evo 0 Posted January 23, 2006 Hello! Does anyone know if you're supposed to use shielded cable for the signal wires on a narrow band, 4 wire Lambda sensor? Just as a long shot, does anyone know whether all Ford NB sensors use the same electrical connection and if it's possible to buy the plug that needs to go in the loom? Cheers! Alex Share this post Link to post Share on other sites
petert 554 Posted January 23, 2006 Hello! Does anyone know if you're supposed to use shielded cable for the signal wires on a narrow band, 4 wire Lambda sensor? Just as a long shot, does anyone know whether all Ford NB sensors use the same electrical connection and if it's possible to buy the plug that needs to go in the loom? Cheers! Alex Yes, it should be shielded as it's only a very low voltage, 0-1V. Share this post Link to post Share on other sites
M3Evo 0 Posted January 23, 2006 Turds. I've got a convenient spare 3 wires into the engine bay, just right for the sensor and heater relay, but none of which are sheilded Ho well, better that I know now Cheers Peter! Share this post Link to post Share on other sites
madspikes 41 1 Cars Posted February 9, 2006 I though that the sensor wires are +12 and ground, and the other two are signal return wires on a which require a differenal amp, eg you measure the voltage between them and so any noise appears on both an thus is canceled out. If this is the case you need twisted pair cable. Share this post Link to post Share on other sites
pugrallye 0 Posted February 9, 2006 no need to shield the heater wires though Share this post Link to post Share on other sites
M3Evo 0 Posted February 9, 2006 no idea TBH but the NB sensor seems to work with just twin core shielded cable. However, I wish I hadn't bothered now as the thing's useless for mapping! Just sitting at idle and looking at the readout, it says massively rich (all the LEDs on for rich), so I tap -ve fuel 34times and this brings it down to 3LEDs in the rich bit not on. Save this number to the map and press -ve fuel once more. The reading plummets to about 1LED on in the lean bit! The things really are just a switch with no real accuracy! Anyway, guy's coming over tomoz with a proper Wideband sensor etc. so we can see what's what Cheers guys! Alex Share this post Link to post Share on other sites
Greenys_meanies 0 Posted February 10, 2006 The things really are just a switch with no real accuracy! No need for shielded wires from my experience. A lambda sensor is a sort of switch if you could put it in simple terms. Most lambda sensors read 0.9 - 1.0 volts rich and about 0.2 -0.3 lean with a mid point about 0.5 volts. they do indeed switch, not like you you would see it on a multimeter though, it switches too quick. ( good way to check if it's duff!) Share this post Link to post Share on other sites
pugrallye 0 Posted February 10, 2006 (edited) hmmm lambada wont cut it til 3k revs heater has to be operated first! and lambda emits a square wave pattern, which shouldnt peak above 1.01V on a square wave, should get a steady enough reading froma multimeter, unless your tapping into heater circuit Edited February 10, 2006 by pugrallye Share this post Link to post Share on other sites
petert 554 Posted February 11, 2006 It's much easier to read an analoque meter than a digital meter. Make yourself a 0-1V meter (by using an ammeter and a resistor). Calibrate it off a known voltage. Then you'll be able to read the 0.6 - 0.9V range easily. Share this post Link to post Share on other sites
petert 554 Posted February 11, 2006 If you have a 4 wire sensor (with heating element - white wires) it will work from idle, providing it's close enough to the engine. If you place it down the back there won't be enough air flow at idle to get a reliable readout. If you can get the maps between 0.6-0.9V (approx. 14.7:1 - 12:1) it will save you a lot of time on the dyno. Share this post Link to post Share on other sites
veloce200 3 Posted February 11, 2006 What ECU are you using? I mapped my Emerald on a narrow band using the Lambda data logging feature. Aimed for over .9v under power then added a bit more fuel. I appreciate wide band is better but mine is substantially quicker than when it ran the std ECU and has been running reliably for a year. Trying to map on the lights alone is tricky as you say they switch very quickly but the data logging gives pretty consistent results Share this post Link to post Share on other sites
M3Evo 0 Posted February 11, 2006 Mine's an Emerald too, did you set the datalog to give speed and load sites, or actual readings in RPM and %throttle? Unfortunately, my throttle pot melted yesterday (I think) when a guy was here helping out with a WBO2 sensor Also found some oddities in the map I've got in that it had a MAP sensor table that took fuel away under high vacuum conditions :? Seems like a bit of a bodge as it was reading rich under certain circumstances for a given speed/load site, and lean under different conditions for a certain speed/load site! Share this post Link to post Share on other sites
petert 554 Posted February 11, 2006 I've done it with Haltech, Autronic and the std. Motronic ECU. The std. ECU won't go outside of the 0.6-0.9V range unless on overrun. Over 0.9V is definitely conservately rich (in the 11's) and if it's more than 1.0V you are drowning it. There should definitely be less full fuel under high vacuum. At 3000 RPM for example, you might have 3ms @ 50kPa (80 km/h cruise), and 6ms @ 0kPa (WOT). Share this post Link to post Share on other sites
veloce200 3 Posted February 12, 2006 I've done it with Haltech, Autronic and the std. Motronic ECU. The std. ECU won't go outside of the 0.6-0.9V range unless on overrun. Over 0.9V is definitely conservately rich (in the 11's) and if it's more than 1.0V you are drowning it. There should definitely be less full fuel under high vacuum. At 3000 RPM for example, you might have 3ms @ 50kPa (80 km/h cruise), and 6ms @ 0kPa (WOT). thing is with narrowband is the output goes flat just rich of stoich. So it's hard to know if you get 12:5 :1 for optimum power. certainly i play mine safe. Share this post Link to post Share on other sites
