I have A 1998 F-150 NASCAR edition with a 4.6 triton.Out of the blue,The check engine light came on & started blinking.It keeps coming up as a #3 Misfire...Then the airbag light came on & stays solid...The truck just turned 100,000 miles.Ive replaced the Injectors,Coil pack,Plugs & Wires,Fuel filter,Even the IAK module,I also did a fuel pressure test,And nothing is working...I need help

 

I think you may want to do a cylinder compressure test on all but mostly #3. A misfire code can happen if your missing fuel, spark, or power from that cylinder. []