Offroad Trailblazers and Envoys

Oil Pressure Switch

Something not working right?

by DirtyBacon04 » Thu Sep 17, 2015 2:35 am

Well, I had a bit of a scare on the drive home this morning. Got stopped at a red light and happen to notice the "Check Gauges" light illuminated. Sure enough, oil pressure was at zero. Uh-Oh. I was expecting to see a big puddle of oil on the street. Luckily, that was not such. Checked oil level, not on dip stick. Added a qt to bring it half way up stick. Still dropped to zero at idle, but would increase with RPMs. Made me think it was an electrical issue, probably the oil pressure switch. So here's my process:

Tools/Supplies:
-13mm socket for oil pan skid plate and drain plug
-27mm deep well socket for oil pressure switch
-Fresh oil and filter
-Dremmel or other cutting device (optional)

Cost: about $40 for switch. your choice on oil/filter


1) Raise vehicle in a safe manner if needed or desired.

Image

2) Removed Oil Pan Skid

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3) Drain oil and remove filter (Optional- It is possible to do this without draining oil, but removing the oil filter gives you a bit more wiggle room, and let you inspect filter to make sure there isn't an underlying sludge issue causing your switch to fault.)

4) Unplug oil pressure switch, which is mounted above oil filter.

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5) Use 27mm deep well socket to remove oil pressure switch which is mounted above filter

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6) Put new switch in, replace oil filter/plug, fill with oil, drink a beer.



I then cut open my oil filter to check the element. Seeing that there was no sludge put my mind further at ease.

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If there is sludge on your filter, just refill with conventional oil then change in 30 days. Inspect filter again. Continue until there is no sludge.

Hope this helps someone who got the same scare I did seeing the needle at zero.
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by HARDTRAILZ » Thu Sep 17, 2015 8:06 am

Nice write-up.
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they've always worked for me.
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by CHEVELLE598BB » Sat Sep 19, 2015 1:24 am

My oil pressure switch finally went a few months ago. It had been leaking a small amount for quite a while. Towards the end it would stop working everyonce in a while. Replaced it with a new ac delco sending unit and its good as new.

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by v7guy » Sun Sep 20, 2015 12:55 pm

thanks for the write up, def a nice addition.
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