Anyone have Experience with 5.7L GM Vortec?

[stingray1]

Tried that also. Today we tested ignition switch and tried new crank position sensor with no improvement. Had ignition control module tested (good) also. That module should be a pulse from PCM on white wire, but instead, itç—´ grounded out inside the PCM continuously. Have decided to order a pre-programmed PCM.

Sounds like your on the right track.I had the same problem,pulled the ignition control module took it to Auto Zone it checked good so I put it back in,after weeks of troubleshooting I installed one out of a junk distributor and it fired right up. Good luck

 

[hawkeye08]

If I recall, fuel pump relay is energized for cranking, but then has to have oil pressure for relay to work. It is located behind the distributor I think. Might be something with oil pressure sending unit.

 

[HHR]

If I recall, fuel pump relay is energized for cranking, but then has to have oil pressure for relay to work. It is located behind the distributor I think. Might be something with oil pressure sending unit.

Fuel pump relay is not being energized for the 2 second prime either.

 

[thepumpguysc]

I had a similar problem.. thought it was the fuel pump, 200.00 later, nope, not fuel pump, still wouldn't come on..
The engine would spin & spin, no fuel..
Finally called a buddy that's an electric genius.. he gets in, turns the key switch & says, I know what the problem is..
It was the "hot wire" UNDER the fuse block in the engine compartment.. he fixed it for .35 w/ a wire connector.
Are you missing any lites on the dash when you turn the key to the ON position??? maybe the "engine" symbol??
THATS HOW he knew what the problem was.. no "engine" symbol.. no power to computer..
..just a thought.. hope you figure it out..

 

[houstonscott]

They are notorious for bad cams....

 

[BKBoiss]

For what it's worth, to shorten a LONG FRUSTRATING four month story, my wife's 03 Tahoe was giving us all sorts of issues. Turns out one of the main computer plugs had green inside on the pins.

 

[HHR]

Update:
Ordered a computer off Amazon on Friday evening for $90.
They programmed it to the ViN number and it arrived Wednesday morning. Plugged it in and the truck started right up and runs great!

 

[Gale Hawkins]

Update:
Ordered a computer off Amazon on Friday evening for $90.
They programmed it to the ViN number and it arrived Wednesday morning. Plugged it in and the truck started right up and runs great!

Awesome find and update.

 

[hawkeye08]

Update:
Ordered a computer off Amazon on Friday evening for $90.
They programmed it to the ViN number and it arrived Wednesday morning. Plugged it in and the truck started right up and runs great!

The Interweb is a wonderful thing

 

[crashz]

Nice work HHR!