I recently (250 miles ago) installed H/C, headers, DR timing chain, LS6 intake, and LS6 oil pump. Yesterday it was tuned and ran fine, but today i got in and started it up and it had NO OIL PRESSURE. The oil sending unit at the back of the intake is new and was installed with everything else. Do you guys thind the tune could have affected something or was it just coincidental that it happened after the tune, and if its not the tune what else could it be.

 

The tune had nothing to do with o pressure I am sure just coincidental...someone else just posted this recently, and actually had a bad ported ls6 oil pump. I would say unfortunately, you are stuck either way removing it and making sure you have the o ring seated etc, and if so I say bad pump...

 

Two things, are you sure you had full oil pressure yesterday? If so that would rule out the o-ring in the oil pump that goes to the pickup. Another easy check (I did this once), reach back behind the intake and feel for the oil pressure sensor. Is it in place or is it wobbly? I snapped mine off the sensor before and it went dead. Another check to see if it's priming up is to see if there's oil on the top side of heads and down the rockers. With 0 PSI I would hardly expect everything to pump up enough to get a lot of oil up there. There are a couple other ways to check for oil pressure, but check the basics first.

 

Pump, o-ring, sending unit, guage, etc.

 

I've never run an engine w/ no oil pressure, but don't they complain pretty loudly? Did your car sound like armagedon, or did it sound normal? Just a thought.

 

well it sounded pretty loud, but the cam i installed is pretty big so i don't know if it was just in my head because i knew there was no oil pressure or if it really sounded different. Any other things i can look for.

 

Well, since you just installed a new LS6 pump not to long ago, it may have taken the 250 miles to work out the o-ring if it wasnt installed perfectly. But there can be so many other things wrong than the o-ring, its just the most common after a pump install.