No oil pressure on gauge?

Okay, if you're saying there's no oil pressure showing on the gauge (which is what it sounds like you're saying), I would first look at the oil pressure sending unit. If that isn't the problem, it's likely you could have a faulty gauge itself.

If you had no oil pressure at all (which I highly doubt) you'd have much bigger issues, trust me.
 
X2 to Chris's above comment. The TJ's oil pressure sender has been giving problems since day one, it's one of the more commonly replaced items in a TJ. My '97 TJ's oil pressure sender went bad at 11pm on a dark remote road out in the middle of the desert when the TJ was still nearly new. Scared the crap out of me seeing that bright red light and a zero oil pressure indication but after killing the engine immediately and checking things out for a few minutes (did I say it was DARK and lonely out there lol?) convinced me it was nothing more than a glitch with the oil pressure sender. Replace your sender with a Mopar (no, not one from Autozone etc.) and it should be fine afterward.
 
If you actually have no oil pressure... you will hear things like lifters clattering in the engine. If the engine sounds normal... probably a sender/gauge issue, not an oil pressure issue.

All that said it is amazing how far mechanical things will go without oil. We had a car which the dealer forgot to put oil into the transmission... plug was in but no oil.... we drove it 1200miles before it locked itself in 2nd gear... and we still drove 100miles to the closest town.

Some company.. ptotech????? did a half hour TV paid advertisement to advertise their oil additive. They drove the cars 100s of miles in LA summer heat with no oil. Apparently you can do that with any old car as long as the cooling system is working.
 
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Some company.. ptotech????? did a half hour TV paid advertisement to advertise their oil additive. They drove the cars 100s of miles in LA summer heat with no oil. Apparently you can do that with any old car as long as the cooling system is working.

Serious? That's pretty unbelievable, but I'll believe it if you say it happened!

I'm not sure how the hell that's even possible though!?
 
OP, my vote is for the sending unit. The gauge itself could be bad (bad stepper motor in the gauge cluster), but that is must more unlikely than a bad oil pressure sending unit which seems to be a fairly common thing with these rigs.
 
Serious? That's pretty unbelievable, but I'll believe it if you say it happened!

I'm not sure how the hell that's even possible though!?
Chris, we all think catastrophe when oil pressure drops. Me, I would shut the engine off. But if you had to keep going, medical, war, life... just know an engine will run for hours without oil.

The TV ad is on record.
The miles we put on our '72 Cortina... fact, I was there.

Coolant, temperature will kill a motor fast.
Lack of oil takes much longer... much longer.
 
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I fully believe the Prolong ad was a scam. Everyone I talk to says even without
Prolong any engine could do what the half hour TV ad shows.

Takes a long time for any engine to die from a lack of lubrication.
 
That claim about running the engine without oil was done by Prolong, I remember it well. It was a scam. Start reading about half way down at point #3 at www.autoblog.com/2010/11/05/automotive-alchemy/

Good article! I personally don't believe any of these magical bullshit additive elixirs work at all. It's 100% pure snake oil in my mind.

Looks like those guys ran the engine for 13 minutes without oil. Even that to me is pretty amazing.
 
The CU test showed two identical engines, one after the Prolong additive and one without it, both failed in 13 minutes after 5 miles after they drained the oil.
 
The CU test showed two identical engines, one after the Prolong additive and one without it, both failed in 13 minutes after 5 miles after they drained the oil.

Yeah, but that's still amazing that an engine could last even a minute without oil in it. I was always under the impression with no oil in an engine it would fail almost instantly.

I guess it's the remaining traces of the oil that didn't completely drain out that allow it to go for 13 minutes.
 
What's it mean if you have 65 pounds of oil pressure and you're running like 1800rpm?
It means you're running a newer TJ where the gauge isn't showing the true oil pressure, it's just showing a mid-scale reading to prevent people from panicking when the see the oil pressure varying up & down as it does in reality. In reality, your engine is probably running 20 psi or thereabouts. 10 psi per thousand engine rpms is rule-of-thumb for acceptable oil pressure.
 
At minimum I would run a cluster diagnostic to confirm the gauge is operable. If you have not run the diagnostic before just hold the trip meter reset button down and turn the key to the run position (not start). All your gauges will then actuate thru their ranges if they are operating correctly.
 
At minimum I would run a cluster diagnostic to confirm the gauge is operable. If you have not run the diagnostic before just hold the trip meter reset button down and turn the key to the run position (not start). All your gauges will then actuate thru their ranges if they are operating correctly.
When my oil pressure sensor went out it was showing 75-80 psi. So it should be working unless it broke in the last 5k miles
 
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