Quote:
Originally Posted by oak2001raid
...I can hear the pump kick in when It wont start, but Im getting very low 20psi fuel pressure...
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This could be an important clue but, like I mentioned, it could be a poor electrical connection causing it. The electrical connector at the fuel pump module is a known problem area. If the connection loosens up from vibration while driving, the terminals get hot from the high resistance and melt the connector. Also, as the pump motor wears, the motor draws more current and the higher amperage draw creates heat and adds to the connector problem. It also causes the motor to wear faster contributing to its own demise. Eventually the connection burns to the point that the motor can no longer get battery voltage and quits totally. Replacement fuel pump modules come with a new style connector. They supply crimp connectors for splicing the new connector to the existing vehicle harness. DO NOT use the supplied connectors. Solder the connections and use heat shrink tubing to "weatherproof" the connections.
The fuel pressure spec for the CSFI engine is 60psi to 66psi. The poppet nozzles at the intake ports require 40psi before they will open and squirt fuel so anything less than that, the cylinders will not receive any fuel. Typically on a cold engine, if fuel pressure drops below 60psi, it will be hard to start and there will be performance issues when it does run. If fuel pressure drops below approx 55psi, you can usually get it to start by spraying some carb cleaner in the throttle body, but again, there will be performance issues when it runs. If fuel pressure drops below 50psi, even the carb spray might not get it running.
If the fuel pump is original at 135,000 miles, an "educated guess" would be that a faulty pump is what's causing the problem. Bottom line is that without a complete diagnosis, it's a $300 guess
Hope this helps.