MAF sensor Voltage..

[Nismo_Freak]

If your looking at the plug from the front of the car, it's the left most area of the connector.

Voltage should be around 1.3 - 1.7 volts at idle, for a stock n/a motor the voltage should be around 4.0 at 4000 rpms.

[corn322]

nismo, so the voltage from the maf correlates directly with how much air is physicaly flowing through the sensor?

and what is the upper limit for the maf on a '90?

[Nismo_Freak]

Roughly yes... the MAF senses air flow from an electically heated wire. It's constantly being heated by the current however the wire is in the direct path of the incoming air. This cools the wire, the more airflow the greater the cooling. The temp difference is noted and sent as a signal.

If you are lucky enough to be able to tie in an OBDII computer into your car you can see alot of parameters such as MAF voltage, coolant temp, TPS signal, etc. It's an excellent tuning tool and diagnostics as well.

For the 90 MAF. I'd change it out after about 240rwhp. The MAF will lose it's resolution causing un-metered air to sneak by. It also will become a restriction in the system. Once you build the KA and move up in the boost spectrum your gonna want to either move to a reprogram, piggyback, or standalone system with AT LEAST a 300Z MAF.

[corn322]

yeah, it does have kind of a small inner diameter... could a maf from a 300 plug right in to the car?

[Nismo_Freak]

Two main things.

1. Your piping might be too small to support the Z32 MAF's size (76mm diameter... roughly 3")

2. Your ECU is not calibrated to use the Z32 MAF, hence it must be flashed with the correction.

[corn322]

ah. thank you.