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James5
27-07-2011, 12:30
Anyone tried one of these (link @ bottom) to give a narrowband signal from a wideband Lambda. I have an AEM wideband kit and it will not allow me to have a narrowband signal and have wideband signal at the same time it's either one or the other :crap:. Typical I can't fault the AEM kit at all other than this lack of additional analogue output's were as the Innvoate LC-1 will allow you to do this.

Basically my car once warm has an idle afr of 10.8-11.1:cry: and sometimes get's so rich bloody thing dies. On cold start she sit's nicely @ 14.7- 15.0 and I believe when you first start the car this is open loop and relys on engine Coolant Temp Sensor (CTS) and Air Intake Sensor (AIS) once slightly warm after only about 10sec's it switches to lambda then relies on the OE lambda sensor. As I am not using the OE lambda and I really don't want to have to take the F7p turbo downpipe off to get another bung welded on as it's a pain in the arse to fit the downpipe back on I am going to use the attached link and T into the wideband signal wire and use it to give my ECU it's 0-1v feed it needs (0v is lean & 1v is rich) so I can still monitor my afr's, basically I have no feed at present as no OE lambda plugged in so 0v so ECU is throwing loads of fuel to richen it up:crap:

Unfortunatly you can't just take the signal feed from the wideband and plug it in as the signal's are very different.

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Scoff
27-07-2011, 20:35
Are you using the analogue output for something else james ? P4 will simulate a NB probe without disrupting the wideband display on the gauge.

But if your using the white wire already, and you don't want to install a second boss then you could fudge up a variable voltage on the narrow band input for the ECU.

Find a 5v output on the ECU, maybe the 5v that feeds the TPS or map sensor, then find a ground (from the same sensor will do) and feed those to either side of a 4.7k pot. (volume control, with 3 pins, you know the sort of thing). The middle pin from the pot can be fed to the narrow band input on the ECU. Then, you should be able to set the pot so there's abotu 0.7v on the wiper (output, middle pin). In theory you should just be able to turn the idle closed loop fueling up or down by twiddling the pot !

That's a real bodge mind, and not a piece of advice I'm particularly proud of *lol*

James5
27-07-2011, 23:25
Are you using the analogue output for something else james ? P4 will simulate a NB probe without disrupting the wideband display on the gauge.

But if your using the white wire already, and you don't want to install a second boss then you could fudge up a variable voltage on the narrow band input for the ECU.

Find a 5v output on the ECU, maybe the 5v that feeds the TPS or map sensor, then find a ground (from the same sensor will do) and feed those to either side of a 4.7k pot. (volume control, with 3 pins, you know the sort of thing). The middle pin from the pot can be fed to the narrow band input on the ECU. Then, you should be able to set the pot so there's abotu 0.7v on the wiper (output, middle pin). In theory you should just be able to turn the idle closed loop fueling up or down by twiddling the pot !

That's a real bodge mind, and not a piece of advice I'm particularly proud of *lol*


Chris many thanks for that I read it totally wrong in the AEM manual:ashamed:, just set gauge to PO4 and I have connected the white cable to pin 35 on my ECU which is my lambda not set fire to anything yet. Will see what happens tomorrow will drive the ole girl to work hopefully it would have sorted my rich idle. Bit late to test now:eek:

Scoff
27-07-2011, 23:58
:agree:

James5
11-08-2011, 14:06
Have had to unplug the white cable from the AEM gauge to pin 35 on the ECU as it sends signal to the ECU and causes the car to run megga lean and then die:cry:. When unplugged the car runs nice and smooth ok it's on the rich side but no complaints to drive.

Any idea's? AEM gauge is on P4 setting I am going to try the P3 setting for Autronic Wideband 02.

Does anyone know what type of lambda the F7p standard one is? I assumed a basic narrowband due to it's 3 wires live, earth, sensor to ECU pin 35.


Edit - 16/08/2011 - I am confused I have the fastchips high boost ecu and I have been looking at the Rtuner guide attached is the signal to pin 35 narrowband of llinear wideband?? I still think the signal is narrowband but my AEM lambda must be giving of the incorrect narrowband signal, think my only way around it is to weld another bung onto the D/P and use OE lambda or find someone who can access the chip and put it into closes loop so it relies on engine temp like it does for the first 1-15sec's of the car being turned on afr's are perfect then:D