2000 blazer. 4x4. My oil pressure gauge goes to zero sporadically. Truck running fine. I replaced the sensor/sending unit on the rear of the motor to no effect. I can make the gauge go to zero by rocking the car with a fast right turn. Not with a left turn though. It will also go to zero with a fast stop. Any ideas ?? Oil pump? Bad gauge? Can I put a mechanical gauge in the same hole as the sending unit?

 

Hey thats a very good question, i have the same problem but with my fuel gauge every once in a while it will drop to empty and back and forth and it doesnt work normal hard to gauge how much gas i have in my truck so i guess by miles ran. I think a gauge is cheaper to replace 1st then the oil pump. For me i have to change my fuel sending unit so i have to wait to it gets hot enough to drop my tank on the weekend..Good luck!!!

 

Any other gauges flaking out, besides just that one.
I ask because,
First thing I had to replace on my blazer among a long list of items was the ignition switch power distribution block.
It distributes 12v across all accessories including gauges even the delay dimmer dome lamp will stop working as this thing gets worse.
Eventually the truck will fail all together failing to supply proper voltage to the fuel pump.

I think its called ignition switch module not to be confused with the ignition module found under the hood.

The culprit is in the steering column just beside the tumbler were your key goes couple torque screws if I remember right.
Large groups of wires travel down the column and plug into the main harness connector.

This is a common problem for blazers.
I e-bayed mine for under $50
You probably just need harness not the tumbler alot of parts stores only sell them as kits if i remember right. I do remember it cost twice as much when you get the tumblers.

Look around at other electrical things i thought my truck was possessed by demons until I replaced mine, then she was good as new for a min. ha-ha
good luck,

 

Hey thanks i didnt think about it could also be causing problems with my remote start as well but not sure. I tried looking for it but cant find it if you can help out please let me know.

 

Look for it under the plastic piece that surrounds the keyhole.
Separate the two plastic half tops and bottom covering the steering column.
Its going to hang up around the keyhole but if you twist it hard enough.
The plastic will shear off from behind the keyhole and slide right off,
cosmetically you’ll never be able to notice.
Way easier than having to try and removing the key assembly.
When you get it apart you'll see two torques screws. There a little tough to get at but take your time hopefully you got the female torque tool and you should have no problem getting them out.
I think I got mine out with a 12 point tiny socket.
But I recommend using the correct female torque driver or socket one may work better than the other,
you'll see what I mean, it's a little tight to get at.