I've had my blazer for a few years and I am approaching 120k in miles.
I did a tune up (Spark plug wires, plugs, rotor and cap) at about 85k.
I just replaced the fuel filter. When I start up the beast, sometimes
it runs fine, sometimes when the idle comes down from the start, it
shakes and dies. Lately, it has been shaking and dieing, so I give it
gas for a minute, and that solves the problem temporarly.
I tested the fuel pressure and it is around 55psi running. I havn't
yet busted out my GM mechanical books to verify the normal operating
pressure. I was suspicious of the battery considering it is about 2
years old and I recently installed an elaborate sound system, but I've
been monitoring the voltage and it is normally not below 11.5V when I
attempt to start and the problem is still occuring.
No engine light as of now.
Ideas? Throw them at me!