View Full Version : 1994 SLS 4.6 Oil Pressure Switch Woes

07-14-04, 11:03 PM
I tried to replace my own oil pressure switch and have failed miserably.
1) I needed a 1 and one-sixteenth open ended wrench to get the oil switch off and I did not have one. Went to the auto parts store and got one, but the body of the wrench is too big to turn the oil pressure switch to remove it because there is not much space to turn the wrench because of the front ibeam and the oil pan (or another part of the car - cannot remember). What tool do I need? HELP!!!
2) I was able to disconnect the switch from the wire connections but after I got them separated I realized I was probably not going to get the two reconnected. Why you ask? There is some sort of bracket that resides directly under the switch and it looks like it's tied into the front suspension brace/I beam (?) and there are two screws that go into the oil pan as well that are attached to this bracket. There is not enough room for me to put enough pressure on the wire connections to mate with the switch. The switch has to be put in first, then the connection would mate to the switch. Critique this for me. Removing the oil filter made access to the switch much easier and I found no wire issues. Oil pressure still appears normal. Oil filter was fine but I have bought an AC/Delco one to replace it anyway. What is this bracket and how easy is this to remove? There is not enough room for me to get my hands up in there to mate the switch to the wires ^&^(**^(*)^(^)!!!! Frustrating.
3) I did attach the new switch to the wire connection so that when I started my car to get it in the garage that I would not short out anything else - like the PCM or something else major. I guessed on this and I hope I did the right thing here. I need some good advice. The switch was GM and was about $10. Thanks for the help so far.:helpless:

Geno Castellano
07-15-04, 12:01 AM
It helps to remove the plastic splash panel between the radiator support and the engine cradle. Then you can reach the oil pressure switch by reaching above the engine cradle from the front. Pliers work to unscrew the switch. It's not in very tight.

There's no danger of harming any electronics or anything by leaving the wires to the oil pressure switch disconnected. That's a 12 volt circuit that is pretty benign electronically.

07-15-04, 11:45 AM
Where is the plastic splash guard you are referring to? You're not talking about the large plastic splash guard on top of the radiator/engine compartment are you? Not a do-it-all mechanic so I'll need some specifics.

Thanks for your response today.;)

Geno Castellano
07-15-04, 12:05 PM
Underneath the car there's a large plastic splash panel that covers the area from the front fascia/radiator support/engine cradle. Usually that blocks access to the underneath of the engine except between the oil pan and the cradle. If you loosen the splash panel it opens up a larger area forward of the engine cradle that provides more access to the oil filter adaper area.

07-26-04, 08:02 PM
Here is the rest of the story: I could not get the oil sending unit off. I took it to a garage and they charged me $55 to put it on, part included. I tried using the oil sending socket but could not get the socket over the 1 and one-sixteenth screw head because of the engine cradle bracket. Tried an open ended wrench but had no room to turn it - from the back or front. I did not ask the mechanic how he got it off, but I figure it was one of two things: probably a flexible wrench or when the car is lifted completely off the ground the gap between the sending unit and the engine cradle widens. Don't know and really don't care. Frustrating as hell for such an easy repair. Comments and more thoughts are welcome. The car runs just fine and the Low Oil Pressure light has not come on again since the repair last week. Thanks to all for your help.