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Does recalibrate the MAF table with " load input on board MAP sensor " will give the same affect as if the load input MAF ?

Note : at idle i recalibrate the MAF table with load input MAF the rpm goes higher but AFR doesn't change but when with on board MAP sensor the afr change .

What car and engine do you have ? as well as what ecu ?

Suzuki 4 Cylinder Full bolt in & Camshaft NA - using AEM fic 6 ecu

Are you using a MAF sensor or map sensor ? If the car doesn't have a map sensor your ecu will not have an input as reference and it will not be correct . If you have a maf sensor you will have to use the maf as reference except if you want to use an external map sensor . Regardless of your choice you will have to calibrate while the engine is turned off .

i have both of them .

but im thinking of re calibrate ( rescale ) the MAF Table by using the on board map sensor as a load input

and i wanna know if it okey to do that as the aem fic software let me choice the on board map as an optional for load input.

also i wanna know if it give the same affect as tuning with MAF LOAD INPUT .

The first thing you need to understand is the AEM FIC is a piggyback, not a full standalone ECU. This means the OEM ECU still has a lot of control over fueling and ignition timing. The FIC can manipulate the OEM ECU's inputs, for instance it can send a different MAF voltage than what the sensor is actually measuring. The FIC can also change the injector pulsewidth manually, you have a table that allows you to add or remove a percentage of fuel injector pulsewidth. This can be pretty tricky because you need to keep the OEM ECU happy, most tuners I've spoken to prefer to work with standalones or reflashes. If you have an OBD2 car, viewing the OBD data using an app like Torque (and accompanying OBD-to-bluetooth module) can be very helpful.

If the OEM ECU on that car has a MAF sensor, it is probably using that MAF signal for most of its fueling calculations. The FIC was primarily intended to be installed on setups adding a turbocharger to a car that was not originally turbocharged from the factory. One common problem you might encounter without a piggyback is the OEM ECU will go into limp mode if the signal from the MAF sensor indicates 'too much' airflow. The FIC has tables that let you reduce the MAF sensor voltage that gets sent to the OEM ECU, this tricks the OEM ECU into thinking it is still running a stock setup so you can avoid limp mode... since the ECU is not aware of the actual airflow going into the engine, you will need to add the additional fuel injector pulsewidth manually using the FIC's fuel tables.

When the engine is idling, the turbocharger isn't adding much airflow, so it's best to pass the original MAF sensor voltage along without making any changes. There are some FIC instruction videos from AEM on youtube, here's the one that deals with how to clamp the MAF sensor:

Hope that helps,


Thank you @AEM_SB for the information . it's actually help.

yes my car has MAF sensor .

actually im aware that the fic is piggyback and it for car which adding turbocharger on it. im planning for turbocharger kit later on but for now i wanna tune it as it is to get the benefit of the bolt on + the camshaft.

so what i just understand from you that the MAF TABLE , VOLT (( M )) at fic ecu It's only for reducing the volt not for increasing the volt as the diameter of the intake pipe changed.

as for now im using a bigger maf pipe, around 9% bigger than stock and i was going to add the volt by +9%

but what you're saying means that i have to reduce -9% to make the oem ecu think it's stock setup. is this will work with NA engine or only with Turbocharge . Reducing the volt seems for turbo setup only as it need to add fuel in boost area but what about NA Engine . Any use for Maf Table ?

can you please correct me if im wrong .

also i have few question and i hope to answer me.

1) What about if i want to use onboard map sensor at the load input for maf table. would it give me the same affect as using the maf as load input.

2) What about if i use Percent instead of Volt to avoid limp mode

3) Can i tune the maf table at wot only

4) Do i have to clamp the maf as the vid, or just add the number i want to reduce.