Start-up Ecotality taps NASA technology for a system that can feed a vehicle's fuel cell on-demand. Images: Hydratus at work In a software-driven world, it's easy to forget about the nuts and bolts.

There could be a couple of things going on here. The first is that these engines were old-fashioned mechanical fuel-pump units, so they need to be primed. That involves getting all of the air out of ...

Trouble ranging all the way from bad gas mileage to burned valves has been traced to faulty fuel I pumps. But faulty fuel delivery is often due to some bad condition entirely outside of the fuel pump ...