Oil Pressure Sender

[csavaglio]

What brand/part number are you guys having good results with for an oil pressure sensor?

I replaced mine with a Duralast and it seems to run about 20 psi higher than the original.....so when cold it almost pegs the gauge and when warm, it shows nearly at the top of the gauge at cruising rpm. Idle when warm shows about 2/3 up the gauge and the old sender showed 1/3. Basically, everything shows about 1/3 of the gauge higher than it was before.

The original read ok, but started fluctuating about 10-15 psi at idle when warm and I found some oil leaking into the electrical connector portion.

Thanks
Chris

[WVZR-1]

Originally Posted by csavaglio

What brand/part number are you guys having good results with for an oil pressure sensor?

I replaced mine with a Duralast and it seems to run about 20 psi higher than the original.....so when cold it almost pegs the gauge and when warm, it shows nearly at the top of the gauge at cruising rpm. Idle when warm shows about 2/3 up the gauge and the old sender showed 1/3. Basically, everything shows about 1/3 of the gauge higher than it was before.

The original read ok, but started fluctuating about 10-15 psi at idle when warm and I found some oil leaking into the electrical connector portion.

Thanks
Chris

If you've doubts about your Duralast just make notes of the readings "full cold" and "operating" - return it and mention you've got an issue with it "fluctuation or whatever" and exchange it. Duralast should be "lifetime" at least once. Try the second - compare to the first!

[csavaglio]

It was the original that started fluctuating, which is why I replaced it. The Duralast one reads steady, just very high compared to the original. The original gave good readings (aside from the fluctuations), at least compared to what I've read is considered good for the LT5.

Autozone (and others) list a couple other brands, but I figured Duralast would be the better choice with a lifetime warranty and an actual named brand.

I can get one from GM, but it doesn't looks much like the original and it's very expensive.....almost 3 times the parts store ones.

[Mystic ZR-1]

Ask for AC Delco at the parts store or online.
I went thru the same thing and the AC Delco sender's reading was more "believable". I got mine on line and it wasn"t much more than the Autozone sender.

[WVZR-1]

Originally Posted by csavaglio

It was the original that started fluctuating, which is why I replaced it. The Duralast one reads steady, just very high compared to the original. The original gave good readings (aside from the fluctuations), at least compared to what I've read is considered good for the LT5.

Autozone (and others) list a couple other brands, but I figured Duralast would be the better choice with a lifetime warranty and an actual named brand.

I can get one from GM, but it doesn't looks much like the original and it's very expensive.....almost 3 times the parts store ones.

You mentioned " very high compared" - exchange what you have already paid for and compare the results with the replacement of the same brand. If it's dramatically different than what you have well then you've reason to question maybe the "BRAND" but there's maybe no need to just spend money for "another brand".

Don't know what the gauge requires for resistance values at 0 and the at 80. - Maybe someone knows. I've never investigated the cluster that deeply. Maybe just check the sender as is with a DMM and record those settings and then use a 100 Ohm pot and see what the gauge wants to see for values. I wouldn't think it difficult to trouble-shoot and confirm. Then there's always a mechanical confirmation.

A Wells PS220 which is a direct replacement for the GM 12555492 says this:

•Switch opens 2-7 PSI
•80 PSI - 60-96 Ohms
•40 PSI - 48-70 Ohms
•8 PSI - 20-35 Ohms
•Less than 2 PSI - 5 Ohms max

It appears maybe that most GM are 0 - 100 Ohm likely.

[csavaglio]

I know the aftermarket replacement senders can vary pretty wildly on what they consider calibrated, even if each brand has it's own calibration numbers. I'm going by the original sender in thinking that it's high......and I don't think the actual pressure changed.

On my '96, I had to replace what was a good working sender when I broke the body off putting the intake manifold back on. The new sender reads a about 5-10psi lower than the original, but I considered it close enough and didn't investigate further. I think I used the cheaper Valucraft one on that car.

This one's so high that when it's cold, it pegs it out and anything off idle, it's almost pegged. It makes the gauge fairly worthless.

The Delco unit is showing unavailable at the 3 different part stores in town here....Autozone, Oreillys, and Napa. The dealership wants about $60 for their replacement one, compared to about $25 for the parts store ones.

I wasn't planning on spending extra money on more sensors....I was going to exchange it or return it if I can get one that reads properly. I can ohm out the sender I have and see what it reads, but since I don't have a mechanical gauge to check it, I can't really compare it with any accuracy.

My first step will be to swap it with another Duralast, which is said to be made by Wells and is the PS220. If that one shows the same, I'll try the Valucraft one and see what it shows.

It is possible that the pressure really is that high, but it seems unlikely to me.



Chris

[csavaglio]

Is there an accessible port where I can hook up an oil pressure gauge tool?

Reading about oil pressure senders on the ZR1net site writeup, it was mentioned that there's a calibration screw. Since the new sender seems to react correctly, just reading high overall, I wonder if I have a mechanical gauge as a reference that I can calibrate the sender/dash gauge to match.

Chris

[csavaglio]

By the way, the Duralast PN cross references PS220, but GM 12555492 crosses over the PS245 when I looked it up.

The senders look different...the body on the PS220 is much longer and looks similar to what I pulled (although min had a fatter, metal body) and the PS245 which looks like the Delco sender that Autozone lists, has a much shorter body.

C

[JFFerner]

I've been experiencing the same problem with the Duralast sensor causing the pressure gauge to peg at 80+ lbs. when cold while at idle. This drops to about 60+ lbs. when the engine is warm and at idle. At 2000 rpm when warm the gauge is at about 80 lbs..I installed this Duralast about 6 months ago to replace the OEM unit that kept bouncing between 0 and 80 lbs.

Please post the outcome of your findings, whether replacement with another Duralast or another product affords a cure. Thanks. Jim

[csavaglio]

Jim,
That sounds EXACTLY what my readings are with the Duralast and my original was bouncing around, but not as extreme.

I'll post if I come up with anything. The more stuff I look up between part numbers, the more confused I get. For the record, I have a Duralast PS220 in there now (the one that comes up on Autozone's site).

Chris