Those with the Injen CAI can you help?

[ken in az]

I have a feeling that the internal diameter of the pipe where the MAF sensor sits is not the correct size. I had my airbox out the other night and I measured the internal diameter of the stock peice and got 81mm exactly which is slightly larger than 3 inches.

If the internal diameter of the tube changes, then the sensor will have false readings. Basically more or less air will be flowing through the pipe and the sensor was conly calibrated for that pipe size.

Nissan/infiniti base almost every engine parameter off this single sensor, such as fuel flow, ignition timing, valve timing, power valve, etc.. and if the sensor isn't reading the correct airflow then your mixtures will be off and the timing won't be right.

If someone could pull the intake and measure the internal diameter of the pipe then we could know if that is the case.

Many thanks!