1999 Nissan Frontier XE P0100 MAF Sensor Fault: RPM Drop & Engine Stalling Fix

Model: 99 NISSAN FRONTIER Fault Code: P0100 Posted: 2010-08-20 10:04

I'm troubleshooting my 1999 Nissan Frontier XE (4-cylinder, 2.4L, 205k miles) with a persistent check engine light showing code P0100 — Mass Air Flow (MAF) Circuit Malfunction. The vehicle runs normally at idle, but as RPMs decrease below 2500, the engine drops to around 1000 RPM unexpectedly. During a recent freeway drive, the engine completely died and would not restart for several minutes. I've already replaced the fuel filter and performed an oil change. The MAF sensor appears physically intact, and wiring shows no frays or loose connections. When I unplug the MAF sensor, the engine cannot exceed 2500 RPM — indicating a strong link between the MAF and RPM behavior. I'm seeking advice on potential root causes beyond the MAF itself, especially since replacing it with an aftermarket unit (costing $145) resolved the issue temporarily. I'd also like to know if exhaust system blockage or catalytic converter issues could be contributing factors. Any insights from owners of similar 1990s Nissan Frontier models would be greatly appreciated.