2003 Chevy Silverado Oil Pressure Sender Question?

larryed

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#1
I have a 2003 Chevy Silverado with a V8 in it and just want to know if I need to look for anything special in order to change the oil pressure sender? I know it is the sender because when the engine is hot it works fine. When I first start it up the gauges swings back and forth but no low oil pressure warning and the engine runs fine. Thanks everyone Larry
 
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#2
no...if you are just changing the oil pressure sending unit just take the ols one out and replace it with the new one....pretty simple on that one....Jim
 

nickb2

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#3
Care to tell us which v8 you have? There are three for your model. I know it is the sender because when the engine is hot it works fine. When I first start it up the gauges swings back and forth but no low oil pressure warning and the engine runs fine.

I find this to be quite inadequate as a proper diagnosis. Why not get a loaner oil pressure gauge just to make sure your v8(which one) does actually have proper pressure at specific rpm ranges. Maybe buy a real oil pressure guage on the cheap from e-bay or similar. I prefer auto meter. http://www.ebay.ca/itm/Autometer-2605-Mechanical-Oil-Pressure-Gauge-/231404882071?pt=Motors_Car_Truck_Parts_Accessories&hash=item35e0ce4897&vxp=mtr

Cuz with these electronic ones, you don't get actual oil pressure to meter. Just a signal.

Typical oil pressure for gm v8's are 6psi @ 1000prm 18psi @ 2000rpm 24psi @ 4000rpm

I have fixed more cars than I can shake a stick at. Owned over 25+ cars and I am only 39 yrs old. In every single car that I thought was worth it that I owned. I always kept my trusty auto meter mechanical gauge. Still have the sticker on my old tool chest. It's over 25 yrs old. Testament to the quality of the brand. A mechanical oil pressure unit does not get a short. Is not part of bus line obd2 communication network and will always give true oil pressure.
 

nickb2

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#4
The reason why I doubt your diagnosis is the fact that the PCM should detect a problem in oil pressure sensor and code it.

See ACE0 attachment to see what I mean. Normally on these engines, if memory serves right. If pcm does not get signal from oil pressure sender, it shuts off injection/spark. I could be wrong and getting mixed up with other gm's. Maybe another mechanic member will chime in.

You should have a code similar to this if sensor is actually malfunction or something is amiss in the circuit.
P0521 Chevrolet Description

The PCM continuously monitors the engine oil pressure. The Oil Pressure Sensor/Switch sends a signal to the PCM when the engine is running.

Read more: http://engine-codes.com/p0521_chevrolet.html#ixzz3KPBeoihf


I went with a 4.8l since I don't know what v8 you have. So specify so I can post proper schematics. ;)

I added a flow chart for a P0522 code EOP sensor(engine oil pressure) since this one applys to a 4.8l 2003 chevy. ACE2 attachment.

While very unlikely but not unheard of, this could go to a PCM replacement. Thus my preference for a mechanical gauge.

You can buy an adapter and have both oem electrical and your own mechanical gauge. Something like the picture I attached.
 

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#5
My experience with GM,even with an analog or a digital gauge was just using a 2.5 psi pressure switch in series with a fixed resistor.. A tail-tale sign of this, is that the gauge always go to the same fixed position.

My 454 CID has a real oil pressure sender, at idle and hot, gauge really dips down.
 

Gus

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#6
I doubt pressure is 6psi at 1000 rpms......since it is not an emission problem, that CE light may not come on......Type C code...