98 blazer runs then quits

[atucci88]

my 98 blazer runs but then shuts down completely. i've changed the cap, rotor, coil, ignition module, crank sensor, fuel filter, plugs, wires, pump relay. none of these have fixed this problem. what is causing the issue. this is really starting to get expensive.

[Meccboy]

Do you mean it starts then imediately dies, or just stalls when driving, sort fo whenever?
Any codes scanned?
What else happens when it stalls?

[atucci88]

it just dies randomly. sometimes it'll die right away. sometimes it will run for an hour and die. sometimes it'll run for three day without a problem then dies. no codes come up but if you unplug a sensor the check engine light will come on. checked the fuel pressure and it reads ok except it tends to bleed down if you dont start the engine after you turn the key on.

when it stalls all it does is just shut the motor down. nothing else. no noise or andy thign. and sometime you can turn the key and itll start right back up and others you gotta wait for an hour before it'll let you start it again.

[Meccboy]

OK.
Well, you are going to have to check the fuke pressure when it dies and wont start.
With it bleeding down like you said, it may b the cause. this engine MUST have at least 55 PSI, or it will not start.
Usually though, a failing fuel pump will caue it to lose power before stalling.
If it just shuts down like someone just turned the key off, then i would susect an ignition switch.
The ignition switch feeds power to many of the trucks electrical systems.
Sometimes banging on the bottom of the column under the key will cause the switch to act up. Or remove the lower cover
and tap on it with a small hammer. It is a small, black, sort of box on the right side, under the key.

[chevyman]

i have a 98 blazer zr2 with a 4.3 vortec motor, it starts then immediately dies within seconds, i changed fuel pump and checked filter. what could be the cause. it runs a few seconds longer when primed. u can email me if u like jrgrass@hotmail.com