Oil Pressure Switch???

[Tinkerin_wit_tools]

Has anyone ever replaced an oil pressure switch on a 99 Blazer??? Oil pressure looks lower than normal on the dash gauge and someone told me that sometimes, it is just a failing switch and not the oil pump. Figured I would try to change this out instead of putting more work into it by doing the pump just on a hunch. From what I know, it is somewhere on the rear of the engine block towards the firewall driver's side and you have to do it from underneath the vehicle. Before I buy the special socket and try to tear up my forearms, was just wondering if there is anyone out there with experience in this and could maybe give me some tips, pointers, or whatever.

[DeltaP]

If you want to find out if the pump is working up to snuff without guessing or throwing parts at it you should connect a manual pressure guage into the port the oil pressure switch screws out of and compare those readings with the factory specs for that engine.

[Tinkerin_wit_tools]

Originally Posted by DeltaP

If you want to find out if the pump is working up to snuff without guessing or throwing parts at it you should connect a manual pressure guage into the port the oil pressure switch screws out of and compare those readings with the factory specs for that engine.

Ok. I still could use some help on removal, and since I have to buy the special socket, and don't have a pressure gauge, I figure that it would be cheaper since I have it removed to just buy another pressure switch and replace it anyway. At a local parts shop, the pressure gauges are just as much as the switch. More than anything I was looking for some advice on location and removal.

[DeltaP]

Alot of auto parts stores will rent you the tools needed. I know Pep Boys does. Go to Autozone.com and sign up so you can access their car repair thingy to get the info you'll need. Any more than that you'll have to buy me a six-pack and I'd have to be passin through!

[Blue Bowtie]

Look behind, below, and a little to the left (driver side) of the distributor.

[Tinkerin_wit_tools]

Originally Posted by Blue Bowtie

Look behind, below, and a little to the left (driver side) of the distributor.

Ok. Got the switch today and tried to look from the bottom up underneath the car when I was doing the oil change. No luck. Too many obstructions! Can you tell me how exactly to get to it? Do I squeeze in from the top/side underneath the hood to the firewall? Can I feel it with my hand? How easy is removal since I also purchased the socket for it? I realize the clearance will be terribly small. Besides the socket should I use a cap and crows foot/wobble socket extension? The clerk at parts shop told me it is very delicate, so I apologize for the questions, but I don't want to break it in any way. Now that I have successfully completed oil change, am I able to replace it without doing it again or can I just pop the cap off to allow some air into the system? I know it would have been so much easier if I had a diagram, but I am forced to ask all these questions since I cannot find it anywhere online or when I ask a neighborhood mechanic. For some reason they do not want to divulge any "secrets", just charge you ridiculous amounts of money for labor and parts.

[old_master]

As Bowtie mentioned, driver side, halfway under the distributor. One electrical connector, and you get at it from under the hood, NOT from under the vehicle. Not much room, that's for sure. I usually take the distributor out to give more room. If you opt for that route, make sure it goes back in exactly how you take it out or the engine will not run. PITA to re-time it. If you're not comfortable with it, don't attempt it.

[Rick Norwood]

You might give yourself a tiny bit more room by simply removing the Distributor Cap (and the Plug wires) and pulling them towards the front of the engine, so you can get a better shot at the hex on the OPSU. Before you spend money on a special socket, try loosening it with a cresent wrench first and by hand the rest of the way. This fitting should have a tapered pipe thread, which should come off pretty easy after the first revolution.