blackburn87

Hey everybody, I have a 99 Cherokee Sport with only 93k miles on it to date. It has been well-kept over the past years and until recently I havent noticed anything major needing repair. For the first time this past weekend I changed the oil and replaced the filter by myself rather than having to spend nearly $50 at a shop. By Monday morning I noticed issues with my oil pressure. At idle, my Jeep normally stays consistent at 40 but has been dipping close to 20 recently. On highway, it stays consistent between 40-50 like always. It is just after a while of being on the road that the pressure drops. I have always made sure to keep a steady eye on all my guages, so this issue has not been happening for longer than 2-3 days. Also, I noticed a gasoline-like smell when checking my oil levels on my dipstick. Is this normal? Granted, I have never actually checked the smell of it before so I do not know if the smell is normal. I have heard 6 different opinions on the issues and wanted to jump on this forum to see what is really going on, from true Jeep owners and not techs looking to weezel my money from me. Thanks guys!

blackburn87

Mechanics have said that it could be my PCV valve needing replaced, or carburetor filters needing cleaned, or just a different brand of oil filter besides Fram. As you can see I have gotten about every "guess" that it could be and would like to know if there is an actual issue...

Bustedback

You need a new mechanic, he clearly knows nothing of how oil pressure works or that there is not a carb on your Jeep. The oil should not smell of gasoline, especialy after an oil change. How does the engine run?

ol"blue

First, Welcome to CF.
Did you use the correct weight and quantity of oil? Is is leaking, or is the level low?
Your 4.0L doesn't have a PCV valve, or a carburetor. It has a closed orifice system to rid the crankcase of vapors/blow-by, and it's fuel injected with a throttle body and individual injectors that spray fuel into each cylinders intake port when needed. You might need to pull the valve cover and clean out any build up of gunk that can build up and prevent the system from removing the unburned gas fumes/blow-by that can run down into the crankcase and dilute the oil. JMO
Here's a diagram of the system.

blackburn87

My engine seems like it is running like normal. I used 6 quarts of 5w30 Pennzoil with a Fram filter. Something I forgot to add was that yesterday the oil was higher than normal when I went out to check it before leaving for work in the morning. When I went to a shop, it was more then halfway up the dipstick and kinda smelled like fuel mixed in with the oil.

blackburn87

I don't know if it is normal, when at a stop light that my oil pressure goes down to about 30 when normal is 40-50.

freegdr

get rid of the fram filter no matter what 4.0 dont like them for some reason

freegdr

this is fine

TruckD

.

blackburn87

I finally got a accurate reading on my dipstick with the oil level being just a shade over full. If oil WAS leaking, wouldn't my oil pressure drop lower over time?? 6 quarts was what I read to fill in the Jeep's manual.

blackburn87

Leaving out Fram, what other oil filter should I try?

Bustedback

Oil leaks have NOTHING to do with oil pressure until all of the oil leaks out, then you have no oil for the pump to suck, then you have no oil pressure. Watch this video

Gmaster

At idle, 13 is minimum pressure so your fine. Arnt you suppused to run 10w-30? couse thats what mine takes.

freegdr

every body has there fav i run stp with caster 10 w 30 high mileage synthetic in mine

baloozabub

My 98 XJ just started having this issue where the gauge reads low at idle (parked, stopped) and goes steadily up as you give it gas. Could it be the oil pump is going bad/clogged?
Can a cold air intake make my pressure fluctuate? I just put one on today and that is when I notice the gauge jumping up and down.