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This CANT Be Good...

vortec4800

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vortec4800 Enthusiast

vortec4800

Posted
Posted

So I was driving my truck all day (put over 250 miles on it this afternoon) and it was running great. Pulling ahead of everything at 75+ MPH and feeling like it could go forever. I remember looking at the oil pressure gauge and seeing it at its normal position, all is well.

 

Then after I got home (luckily) I parked it for a while and went back out to take it to the store. I turned it over and noticed a "check oil pressure" message in the little display on the gauges, and the oil pressure gauge was pinned at 0. I thought maybe it was a fluke, so I turned it off and back on again, and got the same thing. I checked the dipstick and there was oil, and the filler cap was there and tight. I revved the engine a bit and it sounded just as healthy as it normally does, but I wasn't sure if lack of oil pressure would be noticable right away in behavior or sound.

 

The night before I was doing work installing another amp to my car stereo, and drilled the fuse for it on the side of the electrical box in the engine compartment near the battery, it didn't look like there was anything to drill into and I didn't feel anything bad when I did. Everything was working perfectly until tonight, which I'm hoping is just a bad sensor.

 

What would cause this and how can I check to determine what exactly the problem is?

toddgotfish Enthusiast

toddgotfish

Posted
Posted

vortec4800

this sounds crazy but

the only that causes the message center to come on is the actual gauge

so your only looking at one sensor and not two

if it wasn't pumping oil; you would def. know it

knock knock knock knock :smash::(:sick::cry:

i'm not sure where your sensor is but def sounds like it

let us know

willfxp Enthusiast

willfxp

Posted
Posted

Just wondering, what is the normal oil pressure level? I looked in my Haynes guide, and it said:

 

1,000 RPM - 6 (psi??)

2,000 RPM - 18

4,000 RPM - 24

 

 

Yet when I look when I'm driving, I'm always at 40-60.

 

Do I have that much leeway?

 

Thanks,

Rotorwrench Enthusiast

Rotorwrench

Posted
Posted

Check to see if the wire is still on the oil pressure sensor. It's on top of the engine in the back where the distributor was on the oder engines. The sensor next to it is the cam position sensor.

Normal oil pressure is 40 to 60, the numbers listed in the manual are absolute minimums.

vortec4800 Enthusiast

vortec4800

Posted
  • Author
Posted

Yes, my oil pressure is always at about 40 - 60 depending on throttle position and such. I'll drive it home today and investigate the switch, hopefully the wire just came off somehow and I can just click it back on.

Shaners Senior Enthusiast

Shaners

Posted
Posted

Most likely a bad wire on the sending unit... or possibly a conflict of interest in the wiring with your new install so check your fuses...

 

Like was mentioned before, if you had zero oil pressure, your motor would self destruct in a few minutes...

 

Just be careful, and investigate your problem...

 

(BTW I had the same problem in my old G20 coversion van, and it was a loose wire on the sending unit)

vortec4800 Enthusiast

vortec4800

Posted
  • Author
Posted

So I got the truck towed to the dealer today, its a good thing I didn't assume it was a sensor and drive it home because there actually wasn't any oil pressure - and they don't know why. Hopefully my engine will still be... and engine... when all is said and done, I'll keep you guys updated as I find out more.

02 Silverado Z71 Enthusiast

02 Silverado Z71

Posted
Posted

Your oil pump failed. You have a LS1-style engine. You have a rare problem. Have them rebuild the engine. For more info, go to www.ls1.com, go to forum, and do a search on "oil pump failures" Get familiar with what you will be talking to your dealer about.

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