So, last week, I noticed the oil pressure in my XJ on the gauge when i first started up, was sitting close to 80... I checked my oil and it was a quart low, so i added one, but it made no difference. once it is warmed up, it will drop to 40 at idle, but giving it some gas, it will jump to about 60-70. I know this is very vague, and I will try and answer any questions u guys have to help me, heh. I just need to know if this may be a sign of something bad, or just normal and i am just noticing it... 200k miles on original engine. just did an oil change over the weekend and it didn't change at all, either... Any help will be appreciated as always! Thanks!

 

Also, is there an easy way to verify my gauge is working correctly? Don't want to assume the gauge is 100% accurate, heh.

 

One way to check your gauge is to remove the oil sensor ,and hook up a mech. gauge there and see what it reads if its a different reading you know you need to change your oil sensor. good luck

 

Id just replace the oil pressure sending unit, on my 1992 its right by the oil filter and just screws right in,very easy about 12 or 13 bucks at autozone... mine startleaking oil out of the sending unit when it started to go bad

 

yeah, replace the sending unit. mine was doing the same thing and i bought a new one. now it works perfect. took about 5 mins to change out

 

WOW .. I wish mine had oil pressure like that. Once my 1993 4.0 cherokee ( offroad use only ) gets warm, it has ZERO oil pressure ... literally ( aftermarket oil pressure gauge ). If I run the RPM's up to around 4.5 grand it gets a pound or two. I've been offroading it like that since I bought it 3 years ago and she hasnt quit yet.

 

Thats way your newbies cause you dont read the whole ? or you dont understand that many words all together. He will replace the sending unit still with me but he also wants to check it out at the same time thus the mech. gauge I hope I didnt go to fast 89xj4x4 and knoxjeep sorry if I did , Dont Answer anything if you cant do it right.

 

Don't change a thing, that is perfectly normal. You have a mechanical oil pump that pumps more oils as the RPMs increase, thus increasing your pressure. 80 at start up is great, and 40 at idle is too. Everything is fine. BTW, you will not notice a difference in pressure from adding oil, unless you ran it out. Then it would show 0, or very low pressure, and when you added oil it would go back up. You NEVER want to starve the engine for oil! Bad things happen!! LOL!!

 

the stock gauges are all electronic,they are good for what they are,like said earlier if you want a true reading you need to go mechanical on your gauges.Mine has 264,00 on it my stock guage says cold idle about 40 to 60 psi,hot its about 20 psi,that also depends on oil and its condition(clean/dirty)

 

I appreciate all the answers! I am gonna hit the auto parts store after work for a mech. gauge to verify, then replace if needed... I figured less oil would show less pressure, but didn't want to assume it, heh. I was more worried maybe the pressure was too high and i may blow a gasket or something, lol.

 

I haven't seen anything in this thread that says "it's time to R/R the sending unit"...??

 

Rich - relax dude!

 

What viscosity oil did you use when you changed the oil? X2 on checking the sending unit but if your oil pressure IS that high and you recently changed your oil the wrong viscocity may have been used.

 

Mine is 40-60 cold, then 20-25 idle hot. I put 5w30 in a couple weekends ago, is 5w a good viscosity? I am in FL too where it is hotter than s**t.

 

well, it was doing this prior to the oil change, and it started doing it mid last week out of the blue... i changed the oil to 5w30 for the summer here, will be changing again in the fall to 10w40... i can't imagine the oil is the issue, but i am always open to anything, heh.