danastadelman

I just purchased a 89 Cherokee Pioneer I6. Has 215k on it.


Ive had it for about 2weeks now. Im starting to notice little things that make me a little worried.

#First: My oil pressure reads 18-20 when cold at idle and 20-25 when warm. Even when im at higher RPMs it always seems to stay in the same range of 20-25. i dont get much movement of needle, even when i rev up motor, it barely moves needle up.

the thing seems to run pretty good, and the only reason i even started paying attention to oil pressure gage...was because i could swear the first couple of days i had it, it ran at 30-40 when warm or cold.


#second: i got the oil changed yesterday (oil level was full & still pretty clean, hadnt been changed since 205k) but now i notice a ticking noise. i opened the oil cap and it sounds like the lifters ( i think thats what theyre called lol) At idle its a slow tick, and if i give it some gas the tick becomes faster.

The thing seems to run good, other then that ticking noise. Temp is perfect and has lots of power still....



Do i have anything to worry about?

Ive read so many of these forums, that i feel confussed by conflicting info. please help!

Also i need to drive to san diego, ca in Aug.....is that a stupid idea with a jeep with 215k on it??

jeepdreamer

I run Mobile One in all my Jeeps and have had several reach pretty far into the 300k range. The noisy lifter is hard to diagnose for ya, sorry. But if it runs ok and has decent oil pressure and no leaks... drive away. Maybe get the Jeep onto a regular maintenance schedule again and see how it does. Sorry I can't be more specific... hard to help with something like this. Maybe someone else will chime in. FWIW, I drove my 100 dollar (89 4door)beater from Atlanta to Colorado to Moab then Vegas and the same trip in reverse. Couple thousand miles on an untested jeep and never had one issue.

maybe2fast

Yeah 4.0s are alittle noisey.

Synthetic will not hurt it! and will help cleaning the innerds

XRated

I think you would have a hard time finding a 4.0 with hugher milage that doesnt tick. Mine has been sounding somewhat like a small diesel for the last 30,000 miles. Lol.

Run some seafoam thru her and spray about half a can of deep creep into the intake. If your not familiar with sea foam there are multiple "how to" vids on you tube. The seafoam quieted my motor down quite a bit and she"s running like a champ.

danastadelman

So 20 to 25 ponds of pressure is decent? Ya, has no leaks or anything.

cruiser54

Actually kinda low at speed. What brand of oil filter is currently installed on the Jeep?

macgyver35

You said you think you noticed a change in pressure readings on the gauge. Did this happen before or after you got the oil changed?

You should be near 40 or higher at speed. I'm wondering if you have some kind of crap caught in the orifice that feeds the oil pressure sending unit, or maybe something got knocked around when they were changing your filter.

If anything, your pressure at idle should go down as the motor gets hot, not up. Readings as low as 13 PSI at hot isle are within spec. the fact that yours doesn't seem to change much between idle or high, cold or hot has me thinking something isn't as it should be with the sending unit, it's wiring, or where it screws in to the adapter.

cruiser54

Yep. Check this out when getting the name brand of the oil filter.

peep

Your oil sending unit may be clogged or failing (Ive had one blow it's guts out, will leak), or your gauge is faulty. Can you borrow a mechanical gage anywhere and plumb the loaner in right in place of your sender unit.
You should see 25 at Hot idle, 40 - 65 at 1600+ rpm cruisin.
Go with the filter to name brand tip also, it can happen.
For me QState oil, driven hard daily, changed monthly, 572000+ km and rollin, 55-65 psi cruisin, 22-28 hot idle.

danastadelman

i noticed the change in oil pressure before i got oil changed.

i did however notice yesterday, that when i purposely hit rough patches of road or little pot hole, and made the the jeep suspension jolt.....that the oil pressure gague would bounce up to around 40.....

maybe bad sending unit, or loose??

danastadelman

i have just a jiffy lube oil filter.....so nothing special

CPTslackass

I'd put a wix or a napa gold filter on there. My friend works for jiffy lube and said that Fram manufactures their filters. Let's just say that I wouldn't even use a Fram on a lawn mower. :-p

cruiser54

+1,000.

Radi

Probably a bad connection somewhere. There are a number of ground points that could probably stand to be refreshed. Cruiser has a good write up on that.
Clean up the connector on the oil pressure sender, and C101- the big bulkhead connector at the firewall too.

cruiser54

Here ya go.



Renix Ground Refreshing
The Renix era XJs and MJs were built with an under-engineered grounding system for the engine/transmission electronics. One problem in particular involves the multiple ground connection at the engine dipstick tube stud. A poor ground here can cause a multitude of driveabililty issues, wasted time, and wasted money replacing unnecessary components.
The components grounding at the dipstick tube stud are:
Distributor Sync Sensor, TCU main ground, TCU "Shift Point Logic", Ignition control Module, Injectors, ECU main ground which other engine sensors ground through, Oxygen sensor, Knock Sensor, Cruise Control, and Transmission Sync signal. All extremely important stuff.
The factory was aware of the issues with this ground point and addressed it by suggesting the following:
Remove the nut holding the wire terminals to the stud. Verify that the stud is indeed tightened securely into the block. Scrape any and all paint from the stud’s mounting surface where the wires will attach. Must be clean, shiny and free of any oil, grease, or paint.
Inspect the wire terminals. Check to see that none of the terminals are crimped over wire insulation instead of bare wire. Be sure the crimps are tight. It wouldn’t hurt to re-crimp them just as a matter of course. Sand and polish the wire terminals until clean and shiny on both sides. Reinstall all the wires to the stud and tighten the nut down securely.
While you’re in that general area, locate the battery negative cable which is fastened to the engine block just forward of the dipstick stud. Remove the bolt, scrape the block to bare metal, clean and polish the cable terminal, and reattach securely.
Another area where the grounding system on Renix era Jeeps was lacking is the engine to chassis ground. There is a braided cable from the back of the cylinder head that also attaches to the driver’s side of the firewall. This cable is undersized for it’s intended use and subject to corrosion and poor connections at each end.
First off, remove the cable end from the firewall using a 15mm wrench or socket. Scrape the paint off down to bare metal and clean the wire terminal. Reattach securely.
Remove the other end of the cable from the rear of the head using a 3’4" socket. Clean all the oil, paint and crud from the stud. Clean the wire terminal of the cable and reattach securely.
A suggestion regarding the braided cable:
I prefer to add a #4 Gauge cable from the firewall to a bolt on the rear of the intake manifold, either to a heat shield bolt or fuel rail bolt. A cable about 18" long with a 3/8" lug on each end works great and you can get one at any parts store already made up. Napa has them as part number 781116.
A further improvement to the grounding system can be made using a #4 cable, about 10" long with 3/8" terminals at each end. Attach one end of this cable to the negative battery bolt and the other end under the closest 10mm headed bolt on the radiator support just forward of the battery. Napa part number 781115.
　
　
If you want to upgrade your grounds and battery cables in general, contact Jon at www.kelleyswip.com. He makes an incredible cable upgrade for a very reasonable price.
　
Revised 11-28-2011