2003 Gmc Serria 6 Cyclinder

[chevy504]

OKay....My truck started having a random misfire a few weeks ago. I thought it was in need of some new plugs and wires! That did nothing! I ran some fuel injector clear in the truck and it was no help as well. A couple of days ago i parked the truck and the next day i went to start it and it took awhile to get started! after i got it running i brought it to get the converter tested, but of course it had no restrictions! Now it won't start at all! I hear the fuel pump kicking on and checked the filter. WHen its turning over it would make a coughing sound and right when it would go to start it would putter out! Does this truck have a dist. cap? coil pack? could it be any of those???

[rodram]

welcome to the site...

 

Sounds like you have already done some real good diagnostics to sort out what is going on..

 

.. next I would suspect the fuel pump .. even you can hear it there may not be sufficient fuel pressure ... so get the fuel pressure checked.. it should be somewhere between 61 to 66 psi (for a 4.3L Vortec V6)

 

.. based on what you describe, this is very likely the problem

 

.. if you are getting a new fuel pump, then get an ACDelco from a dealer or Delphi from a good parts house .. don't try to save money on other brands...

[Bob D]

Welcome chevy504

 

There was a TSB out regarding distributor corrosion. This was muchly due to AC evap line running directly over distributor, subsequently condensate would drip water on distributor which was not vented properly. This caused me a no-start issue after one year old (fortunately covered by warranty).

Distributor at engine rear is awkward to access, but not difficult if you've patience.

While you're at it, you may want to insulate AC line above (which was the corrective action by GM for problem mentioned above).