harveyf

Yesterday I attempted to start my 944, after sitting for over a month in my garage while I worked on the dash. It wouldn't start. I confirmed the fuel pump was running. Then I hooked up my timing light. I was not getting any spark at the coil high voltage lead. I confirmed 12V on the + side of the coil, so it appeared that the ECU was not activating the negative side of the coil. The battery was clearly getting low, based on the cranking speed. I hooked up my "smart charger" and let it work overnight. When I came out this morning, the car started right up. This would indicate that maybe the battery voltage was dropping so low during cranking that it was insufficient to operate the ECU?

So I know there can be a thousand reasons for a no start. But if your battery is not fully charged, its a fairly simple "rule out" to get the battery fully charged and see if that solves the problem.

jhowell371

JMHO but I think a poor connection or ground is causing just enough resistance (voltage drop) that anything less than a fully topped off battery isn't supplying enough voltage to make the electronics work. Your mileage may vary.

PaulD_944S2

Did you have tach bounce?