I need help! Please! GS400 with AEM FIC-8!!


New Member
So, my SC is installed with all components. The tuner called me and said he is having problems with my FIC; the car is idling really erratic with multiple cylinder misfires. The harness is from Boomslang so I don't think it can be a wiring issue. I bought the universal FIC-8 used so I told the shop to start with wiping out any tune previously in there...and they are still having issues.

As soon as the FIC is disconnected and running only off the stock ECU it runs and idles perfect! Well, very rich at idle and way too lean at boost hence the need for a tune. With this said is it safe to say that there's nothing wrong with my 440cc injectors or any other components such as my fuel pump?

Some things that could be the issue from researching on the net. Let me know if you agree or any common areas that I may be overlooking.dltutuapp.com/ 9apps.ooo/ https://bluestacks.vip/

- Wire not fully pushed in connectors at harness or at FIC
- Firmware not correct for my car with this unit. I see versions 104, 107 110 and more available.
- Problem with car battery, unit not getting proper power thus not providing good enough signal
- Initial setting not correct in FIC.
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New Member
Hopefully you got some documentation that came with your BS adapter harness. You need to find out how the adapter has been wired to work with the stock O2 sensors. You say that once the FIC is fully connected that you get bank rich/lean CELs. What you're overlooking is whether or not the FIC is actually manipulating the O2 signals going to the stock ECU. If the FIC has been tied into the stock O2 sensors then you have the ability to make the O2 signals be whatever you want. Depending on the method of integration and manipulation, you could be getting bank rich/lean CELs because the FIC is making the ECU think there's a rich/lean condition when there really isn't. Are you actually watching your real AFR values using an independent wideband O2 gauge? Shareit vidmate
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