I have a 1998 blazer I acquired that's been sitting for about a year. I went to start it and it wont start. It will however fire on starting fluid. I have put in fresh gas as well as changed the fuel filter. I checked the fuel pressure and with the key on it is a steady 60 psi and while cranking it drops to only about 55 psi. Any suggestions where to go from here?

Thanks
Andy

 

Fuel pressure while cranking is meaningless on these engines. What is meaningful is fuel pressure leakdown. Turn the key on but do not start the truck. Check fuel pressure. It should be 60-66 psi. Turn the key off. Let it sit for ten minutes. After ten minutes the pressure should not have dropped any lower than 55 psi, IIRC. If it does drop after ten minutes then you may have a leak down problem somewhere, either with the injectors, the fuel pressure regulator, or the fuel pump.

 

check the condition of the cap and rotor. The spark may be weak, starting fluid ignites alot easier. May or may not be your issue but its worth a shot.

 

Thank you both for the advice. I will look into both issues.

Andy

 

If you need to replace the cap and rotor be sure and use authentic AC Delco products. These trucks are prima donnas and don't run well with after market ignition parts. Also put some silicone dielectric grease on the terminals inside the cap. That's one of the secrets of a happy, long-lived Blazer.

 

I agree with Toby, he's spot on in both posts!

 

I did a search before asking this stupid question and couldnt find an answer, but where do i plug the noid light in to check for pulses? I am new to the 4.3 motors like these. Much more familiar with the older throttle bodies and then the newer 5.3 motors.

Thanks
Andy

 

If it fires up and stays running with a shot of carb cleaner, (don't use starting fluid) the injectors are receiving a pulse from the PCM. The combination of stale fuel and borderline low fuel pressure could be the problem. What is the fuel pressure 10 minutes after the pump shuts off? Very possible the poppet nozzels are varnished up from sitting.

FYI: The crankshaft position sensor is fine, don't mess with it. The PCM will need to relearn the sensor using a capable (high end) scan tool if you disturb it.