Engine Performance problem
1987 Chevy Truck 6 cyl Two Wheel Drive Automatic 158000 miles
I bought my Chevy a little while and it ran like a tank. Than one day it wouldn't start. It did have a weak spark and gas when it first died but now it has none. I repalced the distrubitor cap, coil, oil and air filters, ICM, spark plugs and the cap wires look good. My thought is if the fuel pump died wouldn't I still have spark? I really am stumped any advice?
My info shows your vehicle is fuel injected. Without the rpm signal, there won't be any spark or injector pulse. The rpm signal comes from the ignition module, but, without the trigger signal, the module doesn't know what to do. The trigger signal comes from the pick-up coil assemble. I'm not telling you to replace anything, right now I'm not quite sure what's causing your problem? Is there B+ at the coil, with the key turned on? I have seen procedures for testing the circuits to this type coil, but, my memory fails me.
As far as the fuel pump, my info shows there is an oil pressure switch in the fuel pump circuit. After you crank the engine enough to bring up oil pressure, that switch closes, and the pump will run, but, it doesn't matter if the pump does run, cause without the rpm signal, the injectors won't pulse.