low oil pressure

[salvatore1]

Originally Posted by Jeffvette

25036935

Thanks - now to get my hammer.

[cedalice]

hi
I have changed the sensor and now the gauge is OK
thanks
now I can look for the others problems ...

[secondchance]

Originally Posted by cedalice

hi
I have changed the sensor and now the gauge is OK
thanks
now I can look for the others problems ...

Sometimes it takes a while to sort it all out if the previous owner had been neglecting but, trust me, it's worth it!

[scottfab]

I have replaced this pressure transducer twice. I finally took one
of the old ones and rebuilt it so it would not leak. I also found an
adjustment screw..... the pics are at
http://www.zr1netregistry.com/ZR1_oilpressure.htm
But the write-up is missing up there so here it is:
<H2 align=left>Oil Pressure Sender Failure</H2><H2 align=left>February 10, 2002</H2>

The oil pressure sender failed again. This is the second time in five years. These devices should not be failing so often. An investigation was necessary. The symptom is when the pressure indicated on the dash fluctuates from 80lbs to 0lbs the back to 80lbs.
Upon dissecting the sender unit I found that it could be rebuilt. Actually reconditioned is the proper term. I did not set out to do this because the part only cost $22. It just turned out that way.
The part is a Neihoff DR4010. I went to four different auto parts stores and they all had the same one. As you will see in the pictures this device has three pins one of which is used for the actual output. The other two are not connected to anything. There is also an adjusting screw that is accessible down through the top of the connector. The access in initially blocked with a rubbery substance which is easily remove to access the screw. This can come in handy later if you want to set the calibration yourself.
As the pictures will show, I first pulled the plastic over up about 1/2 in. The tapped out the center pin. The center pin is the only one that you need to tap out. Then pull off the cover and drain any oil out. You will note that the assembly is a wire wound coil over a rectangular substraight with a center wiper which is moved across the coil to a position depending on the pressure pushing up on the spring.
The sensor it self started to leak when it failed. The leak is small but is enough interfere with the center wiper causing an intermittent loss of signal.
The pictures tell the story. Use the down arrow to select a thumbnail view. If you want to see the thumbnail larger then click on it, but of course you knew that already.

[secondchance]

Originally Posted by scottfab

I have replaced this pressure transducer twice. I finally took one
of the old ones and rebuilt it so it would not leak. I also found an
adjustment screw..... the pics are at
http://www.zr1netregistry.com/ZR1_oilpressure.htm
But the write-up is missing up there so here it is:
<H2 align=left>Oil Pressure Sender Failure</H2><H2 align=left>February 10, 2002</H2>

The oil pressure sender failed again. This is the second time in five years. These devices should not be failing so often. An investigation was necessary. The symptom is when the pressure indicated on the dash fluctuates from 80lbs to 0lbs the back to 80lbs.
Upon dissecting the sender unit I found that it could be rebuilt. Actually reconditioned is the proper term. I did not set out to do this because the part only cost $22. It just turned out that way.
The part is a Neihoff DR4010. I went to four different auto parts stores and they all had the same one. As you will see in the pictures this device has three pins one of which is used for the actual output. The other two are not connected to anything. There is also an adjusting screw that is accessible down through the top of the connector. The access in initially blocked with a rubbery substance which is easily remove to access the screw. This can come in handy later if you want to set the calibration yourself.
As the pictures will show, I first pulled the plastic over up about 1/2 in. The tapped out the center pin. The center pin is the only one that you need to tap out. Then pull off the cover and drain any oil out. You will note that the assembly is a wire wound coil over a rectangular substraight with a center wiper which is moved across the coil to a position depending on the pressure pushing up on the spring.
The sensor it self started to leak when it failed. The leak is small but is enough interfere with the center wiper causing an intermittent loss of signal.
The pictures tell the story. Use the down arrow to select a thumbnail view. If you want to see the thumbnail larger then click on it, but of course you knew that already.

A terrific info! I saved the page just in case.

Thank you.

[Norsky4360]

A GM Master Tech friend of mine told me that the oil pressure gauge sending unit failure was a common problem across the whole GM line back in the late 1980s and early 1990s. Had it happen to us on the 1st day of a 15 day road trip a couple of years ago. He said as long as the oil and water temps were normal and there were no unusal noises coming from the engine we were ok. Replaced the sending unit and haven't had a problem since.

[secondchance]

Originally Posted by Norsky4360

He said as long as the oil and water temps were normal and there were no unusal noises coming from the engine we were ok. Replaced the sending unit and haven't had a problem since.

Wouldn't it be too late by then?

[Norsky4360]

If the water temp spiked and the engine started making noises, yes it would be to late because there was no oil being circulated. But as long as oil was getting circulated the temps remained normal.

When we got to the end of the drive that day I popped the wiring connector off of the sending unit and there was oil in there. My friend told me it is supposed to be dry. I wiped it clean, reconnected it, and fired up the engine. The gauge worked until for a couple of minutes before the connector got wet again and quit working.

The next day (Sunday) we drove for about four hours before finding a parts store that was open. Replaced the sending unit and all has been well since.