1994 GMC Jimmy Electrical

For a start get the ignition switch tested could be failing

Now it will not start at all.

Get a carb cleaner and spray into the carb or the throttle body on an EFI. Did it start and die? If not disconnect a sparkplug wire or 2 and ground it to the engine -have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel problem, check the fuel pressure to rule out the fuel pump and listen to the injector/s are they pulsing.

Fuel pump and Injector/s checks out-start checking the ignition system-power to coil, coil/s itself,distributor pick-up,control module, Cam and Crankshaft sensors.

If both fuel and spark is present-check the valve and ignition timing, this will lead you to problems with compression and valves opening and closing at the wrong time

I checked the fuel pump, it is fine. I am getting fuel pressure to the engine. I checked the fuel pump, it also works fine. But when i finally get the truck started, if you let the engine idle and press down on the gas there is a dead spot at first, then it goes. It is almost like you have to gradually push on the gas. I hate to both you with this, but how do you test the ignition switch, control module, and cam & crankshaft sensors.

But when i finally get the truck started, if you let the engine idle and press down on the gas there is a dead spot at first, then it goes.

Investigate the throttle position sensor and the MAP sensor-test it by the book.