Need an Agreement, Advice or Dianostics

[gmenor]

Sorry had to post this under a different heading. I went to Lowes (3 miles down the road) this morning - truck cranked up fine. Stayed at Lowes no more than 40 minutes and jumped in - no start. Cranks just fine. Did not hear the lift pump engage, oil pressure gauge indicates I have pressure. Two weeks ago sitting at the gas station when engine died but started up right away. The fuel filter changed recently, brand new KN air filter. My thinking - lift pump/oil pressure switch? Any suggestions would help. Just turned 179k. The lift pump and OPS was changed less than 50k.

[charliepeterson]

You need both the OPS and the lift pump for reliable running.
The next time the truck cranks over but won't start try pouring tap water over the PMD. Extra heat soak can keep them from doing their thing. Some members here have had good luck tightening the four screws holding down the two drivers under the PMD.

[Dvldog 8793]

Howdy
My truck had similar symptoms when the pass-key security system went south.
Good luck
L8r
Conley Janssen

[gmenor]

Thanks for the replies. I do keep a brand new PMD in the truck as a back up - in the event of PMD failure. DVLDOG can you be more specific on your reply on how it affected the starting cycle. Another question is I have bought strictly OEM parts, are after market replacement parts any better or is it a crap shoot?

[Dvldog 8793]

Howdy
My truck would turn over and seem to "want" to fire but never go. It had me thinking lift-pump right away but I could hear it running. Also everytime I tried starting I did get a small amount smoke. I just by chance tried a different key and the truck started right. The wonders of modern technology! tongue.gif
I've seen it happen twice since then with different GM vehicles and both times I was able to look like a hero by diagnosing the problem from a lounge chair with a beer in my hand! :D
Hope this helps!
L8r
Conley Janssen