Fun with tubes: Cold air intakes and your MAF

This is by far the most common running problem I see with LH 2.4. Your car will stumble, have inconsistent AFRs or generally run rich. The solution is often a simple one. You cannot attach a filter element directly on the end of the MAF sensor. Well, you can, obviously, but it's not correct. You need a length of tubing before the MAF so the air comes at it straight on. Bosch recommends 12" for a hot wire MAF but I have had success with 6ish as well.

Why does this happen? When the filter element is right on the end of the MAF, air can enter the sensor at jaunty angles and cause turbulence inside. With turbulent air inside the sensor the chances are high that air will swirl past or around the wire, and the same unit of air will be metered twice or more, artifically inflating the load signal to the ECU. Newer MAFs can detect reversion and do not have this problem, so you can run a filter wherever you want, probably.

Pictured is a modded stock B230FT airbox, and a quality B230F cold air intake. Both will provide "clean" MAF signals.