On my 97, there is a grey line near the fire wall that runs along the wiring harness from the passenger to the driver side. It then branches off and connects to the intake manifold. This is where is came loose on my car. Trace the lines around to make sure everything is connected.
1999 Dodge Ram 2500 Cummins Diesel
2002 Harley-Davidson Fatboy
Merlin Extralight w/ Campy Record