Ok, finally getting around to firing up the 4d55 diesel motor from the truck that's been sitting a LONG while, and hasn't run since before I bought it.

Key is on, I hear the fuel pump, and see fuel bubbling out at the injectors when I crack a line at the injectors.

Glow plugs are getting power, and they showed the proper resistance when I removed and checked all of them.

Vehicle turns over when they key is turned.

But it won't start.

Any suggestions?

There's fuel at the engine, and power to the glow plugs, and the starter turns the motor over, so I'm perplexed as to why it won't fire up. Or at least give SOME sign of wanting to start.