larryinkc

I use the O2 modifier as a MAP based load input, in percent mode with the high level drive box checked.

I am using a value of -40% in the table as soon as boost starts.




You put a 1K resistor in the O2 sensor signal wire. The FIC O2 modifier is connected after the resistor. The FIC measures the O2 voltage going to the ECU for 5ms and then modifies it according to the table and sends the new signal voltage to the ECU for 195ms. The modified signal is stronger than the one coming from the O2 sensor after it goes through the resiston and the ECU reads the modified voltage.

I'm not an electronics guy and don't understand exactly how the process works but it does. I have monitored the O2 sensor voltage with an OBDII scanner and watched the O2 sensor voltage change.

radu_rd2

^ I understand all that, but there can't be 'voltage' with only one terminal. It must be the case that the - of the O2 sensor is the same ground with all the others..

larryinkc

You are right the O2 sensor ground is common with the other sensor grounds on my Tib.

I have verified this with a DVM.

Hive

I would need help with the following table:


How do I find out what are the O2 sensor voltage values for different AFR rates which needs to be entered in this table?

ANother question is: Do I have to check that High level drive check box in the setup screen? When does that check box need to be checked and whent not?

radu_rd2

I assume that's for stock O2 sensors. Then viewing as AFR is not necessarily a good idea since they are narrowband, basically what you can reliably get from them is only high-voltage = richer than stoich, low-voltage = leaner than stoich. 0.8v is rich, 0.2v is lean, stoich is about 0.45v. You can't differentiate between AFRs 11 and 13.5 (for example).

I doubt the high level drive makes a difference for us (manual says "this option allows for better AFR resolution on certain vehicles with UEGO style o2 sensors").

If you want real AFRs, get a wideband (like AEM UEGO). You can connect the wideband 0-5v output to the FIC AUX wire, and the program can show a gauge for it and log it.



Sweet larry, thanks for confirming!



Another thing, I noticed you have the O2 on "Voltage" mode, meaning that the map contains actual voltages. I think this means that the actual O2 reading is ignored (except when map entry is 0), which might have something to do with the enriching at idle you mentioned. Basically the ECU is looking for a LEAN-RICH-LEAN-RICH dithering pattern rather than an actual voltage. And even if you provide a perfect dithering pattern ("Fixed" mode), the ECU will sometimes try to change the mixture temporarily just to check if the o2 readings are different (to check that everything is working fine). So what i'm saying is that you should use Percent or Offset mode.

Also, I think that the ECU runs a richer mixture under load anyway (open-loop under load, closed-loop at part-throttle or idle), so O2 remapping might not even be necessary.

Hive

Not sure in which mode my O2 is on FIC in my car. This pic I have used is from the AEM software on my desktop and the settings are not the same as on FIC hence this pic is not actual pic of my setup. I used this pic only to make it easier for me to explain what I need fing02.gif

Thank you for explaining I get it now fing02.gif . Damn I am not sure how I overlooked that explanation regarding high level drive in the manual I've read it so many times that I just overlooked it.

I'll take a look whic mode is used for O2 and make the change accordingly.

elitetuning

whent he car jerks like that its usually too lean of amixture in that area...
where you get the problem add some fuel and see if it changes

Also i was doing some reading on here, but it may not apply anymore. Something about the injector pusles, it sends a different pulse sometimes, and the aem unit couldnt handle it, the people at AEM are supposed to have a firmware fiz for this..

i read about some guy on this forum having that problem, and aem worked with him and made a solution to fix it. If you do a few searches im sure you'll find it as i did.

Hive

Well we have tried adding and taking off fuel in that area and it did not change anything it continued jerking. All of the firmwares have been upgraded/downgraded as by AEM's suggestions. Waiting to see what will happen after putting in z104 slave chip firmware. Supposedlly this will help.

larryinkc

The Z110 firmware is the one that works with the Hyundai ECU.

Hive

I have z110 now in and AEM recommended putting in z104. WHich ECu do you have larry Siemens or Bosch?