I have a 98 blazer that when i let it sit for 8 hrs or so will crank about 5-7 seconds when starting

if i turn the key and and wait 5 seconds then try fires right up. Im guessing some sort of check valve not holding the fuel pressure prime

runs beautiful after it starts no codes and fuel mileage is spot on

during the day when starting and stopping use fires right up and doesnt skip a beat


What ya think

 

Hello,
my 94 did this same thing and I eventually had the fuel pump replaced to fix the issue. The crank times progressively got worse and started happening every time I had to start the vehicle. I would do the fuel diagnose posted on this forum to verify your fuel pressures. Let us know what you find out.

 

My blazer looses fuel pressure when sitting . if i turn the key on and count to say 3 it fires right up and runs perfect . if i drive it during the day it fires right up. i dont beleive it to be the spider there is no fuel in the oil. 98 blazer

 

Several things can cause excessive leakdown. The most common is a leaky check valve in the fuel pump. Check fuel pressure: key ON, engine OFF, fuel pump running: pressure must be 60psi to 66psi and must remain above 55psi for 3 to 5 minutes after the pump shuts off. If leakdown is excessive, the pump needs to be isolated from the system immediately after it pressurizes the system to determine where the leak is, (could be in the plenum or in the tank).

 

*I have combined your two threads on this subject. Please keep discussions on the same issue in one thread.*
Please put your vehicle info into a signature so we don't have to refer back to older threads to know what you're driving. Grab a fuel pressure gauge and follow the steps in 96+ Fuel System Diagnosis.