This issue just started to happen a few weeks ago and it was only in the morning on a cold start and would only happen every few days. The truck would fire right up as usual, but the oil pressure gauge would not move and the Check Gauges Light would come on. I immediately shut off the truck and restart and the gauge jumps straight to normal and stays there. The rest of the day I would not have a problem.

Now this issue has been happening more frequently, about once every five starts (I take at least five trips per day so at least once everyday now) and it doesn't matter if the truck is warm or cold.

When you turn the key to ON and carefully watch the needles on the gauges you can see them twitch (maybe move 1/16" from OFF position) so the gauge is getting power.

I have never tried driving, or revving the engine, with the gauge at zero so I don't know if it will move with higher rpm's. That seems like a stupid thing to do if you actually have 0 oil pressure.

My thought is that it is an electrical issue and hopefully just a bad oil pressure sending unit, but wanted your opinions before i buy a new sensor.

Thanks,
Zac

 

Sounds like the sender. If pressure truly dropped all the way to zero, you'd be hearing ticking all over the place.


I recently changed mine and to put my mind at peace, I bought a cheap gauge from Harbor Freight and tested the pressure. The Mopar senders run about $25 on Amazon.

 

Typical sending unit issue. $7-$11 from Auto Zone with a 2 year warranty and you'll save yourself the headache. I know this from experience. It would take a big piece of sludge or oil filter failure to cause intermittent pressure issues and even then it'd be followed by knocking & ticking and likely wouldn't go away just by restarting the engine.

 

Thanks for the peace of mind. I will buy a new one tomorrow and get it installed.

 

They already answered your question, but I'll jump on board with the sending unit, too. Happened to me about two years ago. Quick fix and no problems since.

 

i have a 1995 dodge dakota v6 3.9 liter. my oil gauge doesn't move. where would the oil sender unit be locate at on the engine.

 

It is usually located near the oil filter

 

The 3.9 is based off of the LA 318(5.2) & 360(5.9) Engines, As such the oil pressure sending unit is located on the rear TOP of the block next to the passengers side of the distributor just behind the intake manifold.


Not commonly on Mopars, generally oil pressure sending units weren't even in the same zip code as the oil filter! The 3rd Gen 5.7, 6.1, 6.2 & 6.4 Hemi engines are all next to the filter (slightly above) but they are the exception for V8s, the 4.7 may have it near as well but I've never had to deal with a 4.7.


We'll go back 64 years staring at the 331 Hemi & all First Generation Hemi engines from Chrysler, Dodge & Desoto all sharing the oil sending unit location with the LA/Magnum V8 engines, they all had it next to the distributor in the back of the block (273, 318/5.2, 340, 360/5.9), likewise the RB Big Blocks & B Engines (361,383,400, 413, 426 & 440) also had it in the rear near the top of the bellhousing support ridges on the engine. The 1 Gen Hemi's had their oil filters technically in the same spot as eachother but with different mountings off the passengers side rear of the block, the RB & B engines had their filter on the front bottom of the drivers side of the block.


Even on the Neon 2.0 4 cylinder SOHC & DOHC (same block), the oil sender was on the bellhousing side of the back of the block, while the filter was next to the drive pulley side.