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AEM FIC tuning question and possible problem

Joined
21 August 2011
Messages
150
Location
Northern Virginia
Finally got the last part in for my BBSC install and started up the car. I did this with the base calibration running with a fuel map created using a new injector size of 550 and stock size of 240. This created a -56% adjustment in the map in the idle range. I am not making any changes to the timing map. Car started but ran really poorly and my AEM wideband gauge showed an AFR of 15 to 18 but quickly pegged to 18. I did some troubleshooting and eventually found that I needed to adjust the fuel map all the way up to -30% to get it running smoothly. This makes it seem like the injectors are either not flowing as much as they should or something else going on as I would think the map created by the FIC should have been very accurate since it is based on the percent change between the injector sizes. Is this somewhat normal with the AEM FIC? I am running RC 550 injectors and I have the BBSC but not running the charge pipe into the intake at the moment so no boost just trying to get the FIC to adjust the injector duty cycle properly. I would like to try to verify I dont have a problem before heading to the tuner so any assistance would be great.

Also does anyone have the settings I should use in the settings screen such as the following: injector response time (400 is recommended but the FIC came with a tune that had 1400 in there), ignition load input (MAF, MAP, or TPS and slew rate), MAF (load input, mode, max voltage clamp)

Thanks in advance,

James
 
Im not a tuner but when I installed the fic my car ran like crap until warm on base map. It was found the wrong firmware was loaded in the fic. I was told the firmware that the fic is shipped with wont work and you have to reflash it with a different firmware. You should check that first if you havent done so already.
 
I'm not an expert but upon immediate startup (ECT cold) it will run in open loop. When warm I believe it will then run in closed loop. Two different modes basically. I don't know how the F/IC differentiates this if it does at all.

Does it idle more "normally" when warm?
 
Not all injectors flow linear.

Further, without an OBD2 Scan tool (assuming your car is an obd2 vehicle) its hard knowing what the factory ECU is doing. In closed loop, the factory ECU is going to adjust fuel trims until it reaches its target lambda at low and mid engine load. Once you go into heavier load it switches over to open loop.

What year NSX do you have?

Regards,
Mase
 
I have a 92 NSX OBD1. I am running the Walbro pump with the stock pressure regulator. I do have the correct version of firmware and checked a couple times to verify (z110). My main concern at this point was the fact the AEM FIC generated base MAP was too lean. It wanted to run the injectors at -56% or so and I need to be in the -30% to get it to idle nicely and have a good AFR. Just wondering is this was normal or might inidicate an issue with my install. Also wanted to get the basic settings for some of the timings etc in the setup screen on the AEM FIC.

Thanks again everyone.
 
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