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No Oil Pressure

Scorps

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Scorps Enthusiast

Scorps

Posted
Posted

Now I know there is oil pressure because this issue has been happening sense last fall. when the truck warms up the oil gauge just stops working dash light comes on but if I had no oil pressure I figure it would have gone boom by now.

 

So my question is do I need a new sender or can I just take the old one off and clean it up and have it work like it was before?

 

(88' 5.0l TBI SBC)

grampadirt Senior Enthusiast

grampadirt

Posted
Posted

I would buy a new sender,oil pressure is one of those things I monitor closely.Check the wiring if you haven't done it already.On my '95 if the gauge shows no oil pressure the ECM won't let it start...protects the engine I guess.Yours must be different?Maybe the gauge is bad but the sending unit is still good? dunno

 

Last year my engine all of a sudden died(while driving up a hill) and would not start,I replaced all kinds of shit without gettin it to start.Then,thanks to this forum I checked the wires going to the sending unit...sure enough,one of the wires had layed against the exhaust manifold,melted and grounded out.All I did was un-stick it,zip tied it back out of the way and VROOM,it started...

kuhl_530 Enthusiast

kuhl_530

Posted
Posted

oil pressure sending unit will cost you no more than 20 bucks, it's well worth the replacement. +1 on checking the harness too, never a bad idea any time you replace an electronic item

Scorps Enthusiast

Scorps

Posted
  • Author
Posted

Cheap that's what I like the hear with this truck being my winter beater. The 305 can blow up for all I care, it give me the motivation to get a 350 :lol:

grampadirt Senior Enthusiast

grampadirt

Posted
Posted
Cheap that's what I like the hear with this truck being my winter beater. The 305 can blow up for all I care, it give me the motivation to get a 350 :lol:

 

 

Hell yes,and do a build thread :lol:

Cowboy09 Enthusiast

Cowboy09

Posted
Posted

Is there any way to test the gauge to see if it's the gauge rather than the sending unit? My pressure, temp, and battery gauges aren't working right, but I don't know if it's the sending units or the gauges.

bill190 Enthusiast

bill190

Posted
Posted

Basically this is somewhat complex. If you applied full voltage to the gauges to test them, this could damage them.

 

And these things have all sorts of different electrical designs. How the oil sending units work, how the gauges work, etc.

 

I think you would be safest to get a GM factory service manual set for your specific vehicle and follow the step by step instructions for troubleshooting this. This would give you warnings to not do something which could damage the gauges if that was a possibility.

 

Then various instrument gauge panels are ALL different! They change this stuff like night and day. In some cases the sensors would provide a ground or a varied resistance to ground to make the gauges operate. In other cases a positive voltage or varied positive. Or a mixture of both depending on the gauge.

 

So I couldn't tell you a general way to test your gauges over the internet and be safe to not damage the gauges.

 

Also for testing the oil sending unit, the factory books would tell you which wire to test, where to place the other wire of the multimeter (ground or positive or to another lead on the oil sending unit with plug disconnected and measure resistance), and would tell you what an acceptable reading would be. And might have you check for a short to ground.

 

The thing is there are many different designs out there for oil sending units. No telling what you have! (Without looking at the manual for your year vehicle.)

 

Basically I would say to get the factory books or have an electrical guru fix it.

 

You can check your fuses...

http://www.dinosaurelectronics.com/Test_Fuse.htm

Cowboy09 Enthusiast

Cowboy09

Posted
Posted

Thanks for taking the time to write all that, I appreciate it. I'll check my fuses since I've got a meter. If that doesn't work out, I guess I'll try to acquire a book for my truck.

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