Oil Pressure

[TheBlackPearl]

I replaced the sensor yesterday and found that the old one did not leak or any visible problems with it. When I started up my Z the oil pressure was exactly the same if not higher. So the sensor was not broken, now what? Is it fine or should I go further?

[csavaglio]

I had several sensors that read the same but much too high compared to the actual pressure on the ZR-1. The parts store one in my LT4 reads on the low side. I would go down to Harbor Freight and pick up a mechanical oil pressure gauge kit. It wasn't expensive and will give you some peace of mind knowing what the actual pressure really is. I want to say it was around 20 bucks for the kit was all the different fittings. The LT5 sensor's in an easy spot to get to to hook up the mech gauge to.

Just because the sensor doesn't look bad and is working, doesn't mean it's calibrated correctly. I tried 3 or 4 different brand sensors before I found one that was calibrated properly for the car and matched the mechanical gauge.

[scottfab]

Originally Posted by TheBlackPearl

I replaced the sensor yesterday and found that the old one did not leak or any visible problems with it. When I started up my Z the oil pressure was exactly the same if not higher. So the sensor was not broken, now what? Is it fine or should I go further?

For grins why not disconnect the electrical connection on what you think is the pressure sensor then see what it says on the gauge.
Does it read zero?

[We Gone]

Just replace my sending unit on the 93 was getting a bit jumpy with one from NAPA, warmed up sits at the first tick mark idle as soon as you touch the gas goes to the 2nd mark or just a bit past and about midway to the last at WOT.

[TheBlackPearl]

Originally Posted by csavaglio

I had several sensors that read the same but much too high compared to the actual pressure on the ZR-1. The parts store one in my LT4 reads on the low side. I would go down to Harbor Freight and pick up a mechanical oil pressure gauge kit. It wasn't expensive and will give you some peace of mind knowing what the actual pressure really is. I want to say it was around 20 bucks for the kit was all the different fittings. The LT5 sensor's in an easy spot to get to to hook up the mech gauge to.

Just because the sensor doesn't look bad and is working, doesn't mean it's calibrated correctly. I tried 3 or 4 different brand sensors before I found one that was calibrated properly for the car and matched the mechanical gauge.

Is this the one?
http://www.harborfreight.com/engine-...kit-98949.html

I'll disconnect the plug tomorrow and see what it says.

[csavaglio]

Yep, that's the one. It's not hard to figure out which fitting to use.

My NAPA sending unit reads the same as WeGone's.....which matched up pretty close to what the mechanical gauge said. As I said, I have a Delco one but I've never tried it. I figured if the Napa one gets weird, I'll swap it in.

[TheBlackPearl]

Do you know the NAPA part #? I picked up the oil pressure gauge, so i'll check it tomorrow.

[csavaglio]

It was Echlin 6677. When I went down there, I took the car, brought a wrench and swapped the sensor out in the parking lot to make sure it worked right on the spot. Funny, but I had them call the manufacturer to give the calibration curve....i.e. X PSI gives Y ohms and it was the same as the junk Autozone and Oreillys senders made by Wells, but what I found when I broke out the multimeter was that the Wells units gave much higher resistance values than correct...65 psi was giving over 110 ohms and the gauge feeds off of 0-110 ohms, meaning that at just 65 psi, it was pegging the gauge full high.

The Echlin/Napa sender gave readings consistent with what the FSM called for and has been working fine since November when I put it in. Since I have the Delco spare on hand, it's pretty safe to say it'll never go bad.

Here's the link to the thread I had going about this issue a little while back....

http://zr1.net/forum/showthread.php?t=21648&page=2

It's worth reading from the beginning.


Chris

[We Gone]

Originally Posted by TheBlackPearl

Do you know the NAPA part #? I picked up the oil pressure gauge, so i'll check it tomorrow.

OP6677

[scottfab]

Originally Posted by csavaglio

It was Echlin 6677. When I went down there, I took the car, brought a wrench and swapped the sensor out in the parking lot to make sure it worked right on the spot. Funny, but I had them call the manufacturer to give the calibration curve....i.e. X PSI gives Y ohms and it was the same as the junk Autozone and Oreillys senders made by Wells, but what I found when I broke out the multimeter was that the Wells units gave much higher resistance values than correct...65 psi was giving over 110 ohms and the gauge feeds off of 0-110 ohms, meaning that at just 65 psi, it was pegging the gauge full high.

The Echlin/Napa sender gave readings consistent with what the FSM called for and has been working fine since November when I put it in. Since I have the Delco spare on hand, it's pretty safe to say it'll never go bad.

Here's the link to the thread I had going about this issue a little while back....

http://zr1.net/forum/showthread.php?t=21648&page=2

It's worth reading from the beginning.


Chris

The one I took apart and then re-crimped together had an adjustment in it.
Link-to-Oil-Sensor