Oil Pressure Sender question

clemsparks

Daily Driver
Aug 28, 2010
35
0
0
Columbia MO
Hey there,

I'm hoping I can get some help on this issue. I have an oil pressure gauge in my '78 Malibu. The plug that I believe to be underhood plug for the oil pressure sender has three wires. There are a couple photos below. My question is...what type of sender is this meant for? It seems like the idiot lights use a two wire sender that is pretty small (I have one of those but think it's probably not right). The oil pressure guages seem to take a one wire sender that is larger and "can shaped". I haven't seen anything yet that I think would fit this plug. I'm probably missing something...or have the wrong plug altogether. Any help?

[I'm piecing together a project that I bought that was already disassembled...so just trying to figure stuff out]

Here are two photos of the plug in question:








Thanks for any help,
Clem
 

clemsparks

Daily Driver
Thread starter
Aug 28, 2010
35
0
0
Columbia MO
Ah...looks like I found my answer in a thread when I started digging deeper ( Correct wiring for oil pressure gauge??? ;). This plug is appaprently for some sort of choke operation. Something I don't expect I'll need.

Now I just need to track down the correct connector or wire for the pressure sender that goes above the oil filter.

Thanks...and hopefully it'll help someone.

Let me know if you have anything to add.

Clem
 
Last edited by a moderator:

MikeB

Daily Driver
Dec 14, 2006
19
0
0
More than likely, here's how it works: The electric choke won't get power (and began to heat up and open) unless the oil pressure switch is closed. Essentially, it's a check to make sure the engine is running.

What year is your car? I am working on a 79 El Camino that doesn't get 12 volts to the choke, and I'm not sure if it uses the above wiring scheme, like in my 82 pickup.
 

LS6 Tommy

MalibuRacing Junkie
May 15, 2004
15,847
1
38
North Jersey
Mike B nailed it.

Tommy
 

clemsparks

Daily Driver
Thread starter
Aug 28, 2010
35
0
0
Columbia MO
To answer your question, MikeB: Mine is a '78 2 door. It was originally a V6 car, according to the VIN.
 

1982 SS

Frequent Racer
Jan 19, 2007
382
0
0
Clearfield, Utah
What's the right part for that two prong oil pressure sending unit? I've got a '81 Monte that had an electrical fire behind the distributor and I'm rebuilding the harness. I'm pretty sure I need to replace the sending unit too, all I can find are the single prong sending units.
 

clemsparks

Daily Driver
Thread starter
Aug 28, 2010
35
0
0
Columbia MO
I'm back with one more question (actually...some further discussion). I've decided this is, indeed a very convenient way to hook up my electric choke. So I need to get a sender to go with it.

When I first looked at the plug in the photos above, I imagined a 3-post sender would be what it plugged onto. But, doing some more looking around, it seems like it's a 2-prong or 2-post sender (like some of the ones in the link 1981Regal shared).

I just want to check with others who have this setup. Is it a 2 prong sender?

Another thread I found that talks about the sender, in case it helps others who are working on this:


In that thread, they clearly show a 3 post sender. But now I'm thinking that is for a car with an oil light and not a guage.

Can anybody confirm that if you have an oil guage there is a 2 post oil pressure switch to operate the choke and then a separate sender to operate the guage?
 
Last edited by a moderator:

t5montecarlo

MalibuRacing Junkie
Oct 21, 2007
4,632
31
48
Lederach, PA
garage-scene.com
With a Chevrolet V8, the factory pressure gauge gets its signal from a sensor on the left side of the block, not by the distributor. The sensor by the distributor controls the electric choke, and in later years I think it also communicates the existence of oil pressure to the computer.
 

Doober

Moderator
Jun 2, 2003
14,704
1
38
Catalina, AZ
www.cardomain.com
Not that it's worth much, but I don't have an electric choke (so no pressure switch). I do have a Grand Prix dash with oil pressure gauge. It's a little mismatched but I'm using the stock sending unit for the '88 pickup the engine came out of. I haven't verified the pressure is accurate (different sending units have different ohm ratings depending on vehicle and oil pressure gauge reading), but I believe it's relatively close. I have the sending unit up next to the distributor, and a plug in the orifice above the oil filter.
 

MalibuRacing.com Gear

Stickers & Shirts!!