Hi guys,

I have a 1995 Chevy Blazer with 4.3 vortec. I replaced the spider about 11 months ago, tuned her up and she ran great until recently. The motor starts up instantly but is missing. I retrieved the p0300 code using my snap on solus. I checked the fuel pressure with just the key on then off and it is about 58 to 59 pounds. Within 25 minutes, the pressure drops down to about 40 psi. Could the spider have went bad again, or could the fuel pump be on its way out? Most articles I have read on this forum state that the fuel pump pressure should be in the range of 60 to 65 psi and I am measuring 58 to 59 psi. Any ideas, or should I look into the electronics of the ignitions?

Thanks

 

58 is pushing it,but it should be alright. Do you still have the cpi or is the newer vortec (black manifold). If its cpi, remove the vortec emblem and you'll see a round sensor. remove it,pull it up and out and you can see the regulator and see if its leaking. If its all clean inside its leaking.

 

Thanks for the reply.. Is the psi drop ok? Some threads state that it is within the time limit and others state that it should'nt drop to 40

 

1995 fuel pressure must be 55psi to 61psi. When you initially turn the ignition to the RUN position, (don't start the engine) the pump will activate for ~2 seconds and shut off. The pressure must be checked while the pump is running, and the engine is OFF. It must remain above 50psi for at least 10 minutes after the pump shuts off. If it fails one or both parts of the test, further diagnosis is necessary. The results will determine what to check next.