Pontiac Repair: 94 Pontiac Grand Am Cranks but wontt start, crank sensor, fuse box

Question
Hi, my nephew's 94 Pontiac Grand Am with a 3.1L V6 and auto trans cranks but won't start. He drove to the store, it ran fine, when he came out it had this problem. I checked for spark, no spark. I checked the fuses and breakers on the edge of the dashboard, all good. I noticed  that about 1/3 the fuses aren't getting power (to ground) with the key on. My thoughts was the ignition switch, but the guy at the parts store said they rarely fail. He hooked up a handheld scanner, but it couldn't connect to the computer. He said the computer might be bad, but my thought is it isn't getting any power. He said something about a crank sensor, could that be the problem, and how do I test it? Thanks.

Answer
Hi Mike:

You did a pretty good job looking at looking at this issue. what fuses are missing power? That is a place to start looking. there is a fuse box under the hood on that year as well I belive by the battery. If your not getting power to the ecm (computer) that is an issue as to why a scan tool will not communicate. BUT those code readers are hit and miss. the engine doesn't need the computer to produce spark the ignition module will do it by it's self the engine computer control the amount of spark advance. An easy check is this with the key in the run position unplug the 2 wire connector at the ignition module (passenger side) the driver side has 2 plugs in it. that 2 wire plug has a black and pink wire. Pink is ignition power and black is ground if you don't light a test light across those wires that's the issue. and back track from there. The ignition power may feed the engine computer as well as the ignition module and you may find that those fuses you were talking about is one that feed both things. check the big uses in that under hood aux fuse box those feed the ignition switch which in turn feeds the smaller fuses in the dash fuse box. I have had a few bad ignition switches on those older Grand ams It's not reall all that un common but I wouldn't condem it untill you look into it further. good luck. Hope that helps you out!