My Blazer would not start so the first thing i did was check fuel pressure and with key on it went to 60psi and held. checked spark and that was fine, so i dumped a little gas down the throttle body and it fired right up. It started and ran just fine for 4 days after that and then would not start again, poured some gas down the throttle body again and it is running fine again. Fuel pressure is at about 54 at idle and jumps to 61 when reved up any ideas?

 

The fuel pressure should be between 60 and 65 with the key on and engine off. It should not go below 55 for 10 minutes, there are no published specs on running fuel pressure. Post back your initial and 10 minute later numbers.

 

One of the most used threads we have:

96+ Fuel System Diagnosis

 

with the key on and the pump running pressure goes to about 63 and when the pump shuts of it drops to 61. After sitting for 10 min. with the key off pressure dropped to 42.

 

A 10 minute drop to 42psi indicates there is a problem somewhere. Sounds like you have an intermittent problem. Checking it when it's working will not reveal the problem, (if it ain't broke, you can't fix it). Check fuel pressure and leakdown when it won't start.

 

Thanks for your help, if I can get it to act up again I'll check it out otherwise I'm just going to put a pump in.

 

If you end up replacing the pump.... use AC Delco or Delphi only, and solder a 10 gauge jumper wire to the pump ground wire at the module connector and run it to a good, clean chassis ground.