Hoffnah1426

recently my 95' 5.0's oil pressure gauge (commonly referred to as an idiot gauge) has been jumping sporadically between Low to normal and even to high once in a while, well today while changing my oil, I put in a new oil pressure sending unit (stupid location) and now my oil pressure gauge just doesnt move at all anymore. any thoughts?

I'd really like to avoid bringing it to a shop, Im only 19 so mechanics doubt me and usually call me stupid and wont help me. (thats not an exaggeration)

any help would be much appreciated

dirtcrew51m

Check the push on terminal, it might be corroded or fell off.

qdeezie

Regarding the installation of the oil pressure switch, you might want to take it back out and ensure that the threads in the block are clean (a small wire brush would work or an engine journal cleaner brush would work even better) and only use a small bit of thread sealant on the threads. Regarding how to apply the thread sealant, it's sorta tricky if you're not familiar with it. Apply it maybe an eighth or a quarter of an inch down from the end of the switch that you screw into the block. If it's too much thread sealant or if it's not applied correctly, the sending unit may not properly ground and you won't get a reading in the dash.

Also, with the oil pressure switch, some are for trucks with an oil light in the dash and some are for trucks with a gauge in the dash. Make sure you have the one for a gauge.

Finally, it is common to purchase a brand new electrical part and have the part be defective. I've had it happen from time to time. Also, I purchased my oil sending unit from Autozone and I've been very pleased with it.

Hope this helps!

qdeezie

Oh, and one more thing. Be sure to use brake cleaner spray in both the block threads and the inside of the connector terminal, to ensure you have a good connection.

Hoffnah1426

Okay thanks guys! I might have went a little overboard with the teflon tape so I'll recheck all that.

Hoffnah1426

yup, dumb girl at advanced auto sold me the oil light sending unit and not the oil gauge one. women.

qdeezie

One thing I've learned over the years is that if it is possible, take a quick second to go to the manufacturer's website and check the part number against what you were sold before installing it. That way, it will save you a lot of trouble with those types of situations. If the manufacturer's site is not available, see what that auto parts store website says (although you can't trust it 100%, it's still a good way to verify).

Sometimes, I am very much guilty of not doing this as well because I assume it's the correct part. Just today, I returned an incorrect EGR valve position sensor because the parts store had the wrong part number listed for my truck. They come in 2 different colors and color does matter with this part. Had I double checked before hand, I would have saved a whole lot of time.

Anyway, that's my take on things. Glad to see everything is working out well for you.

mark_d

I don't know if the dummy light issue in my '91 is still present in your '95, but they put a resistor in the back of the cluster in the oil gauge circuit. If you use a real pressure sender you should remove the resistor for the gauge to work properly.

Not sure what bypassing the resistor does but I'v read about the procedure elsewhere on this forum. My gauge was showing no pressure/very low pressure and I checked it today and it's 50-60 psi.

Good luck!

zzpatrick1

MIne was doing the same thing. Im about to drop the pan and check to see how gummed up the screen is on the pickup in the pan.