Difference between 99-00 MAF and 01-04

[Gtracer]

On a Mustang GT.

I have a 99GT, The OEM MAF is a 4 pin setup and the wiring harness is a 4 wire setup. I recently picked up a MAF off of a 03 GT and turns out it is a 6 PIN MAF.

I notice that my stock MAF from 99' (4pin) only measures the air flow and the temp sensor is a seperat unit from the MAF housing. It seems in 03' they incorporated the temp sensor and the air flow sensor into one unit hence the extra 2 pins from 01 and up.

I am thinking that I can still use the 03 sensor (or I am out $30) depending on which pins on the housing go to which sensor. Does anyone know which pins go to which sensor? We are talking about the pins within the large female connector on the MAF housing.

[LS1Goat]

you answered your own question. the '03 has the IAT sensor built into the MAF (instead of separate mounting on the inlet tube in the '99/'00) and the metering tube was changed for improved flow transfer. and i also believe it may be calibrated for 21 lbs. injectors and not 19 lbs. might be an issue with open loop, but maybe not. the IAT sensor pin wire should be gray last time i looked. and the other extra pin wire is probably a ground or return.

[Jonny00GT]

Per my last Tuner, I believe calibration on the 99-04 mustangs is done with the PCM. Not sure about other years, but I'd assume the same since a lot of the boosted guys are going to the slotted MAF design of the 2005+ cars.

[Gtracer]

Per my last Tuner, I believe calibration on the 99-04 mustangs is done with the PCM. Not sure about other years, but I'd assume the same since a lot of the boosted guys are going to the slotted MAF design of the 2005+ cars.

So I have come to the conclusion I can use the 03' MAF as long as I leave my IAT sensor plugged in.

The PCM calibrates the injector poundage and I have an SCT customer tune....which I know how to work I am just not sure how to check to see what I am currently calibrated at. Anyone know how to check this on an SCT tuner?