1981 VW vanagon turns over but gives no effort to start. whats the problem?

Ive been working on this vanagon for about 3 months now. When i parked it, it was running nicely. it started right up after approximately 4 revolutions of the motor. idled fine. its been 2 months since i started it up and when i turned the motor over it will not even attempt to run. The motor is getting fuel, and spark. the injectors are spraying fuel into the block. im at a loss. i dont know what the problem could be. i was hoping to have a loss of spark or fuel because that would have made it an apparent fix. pleas help me get this beauty back on the road.