97 Cherokee Oil Light??

[Isaac McShane]

Hello, I am new to this forum, but have heard good things about it so here goes:

I have a 97 Jeep Cherokee Sport, and the oil light recently started coming off and on. There's not a lot of pattern as to when it comes on, but it seems to come on more when going around a curve or up or down a hill, and go off on straight-aways. It doesn't seem to stay on more than a few minutes at a time.

There is plenty of oil in it.

In addition to the oil light randomly coming on, a recent pulley noise has started. It sounds like your typical malfunctioning power steering pump, but it really sounds like it's coming from the opposite side of the engine, specifically the a/c motor. The a/c and heat both work really well. I don't know if the sound and the light are related, but they both started at the same time.

I took the belt off and tried spinning all the pulleys. It doesn't seem as though any are lagging real bad. A bearing could likely be going out, and perhaps that's affecting the oil pressure. That's my only guess.



Has this happened to anyone else, and given the clues I've provided, does anyone have any suggestions aside from the shotgun approach like buying random parts, such as the power steering pump and fuel pump?

Thanks a bunch.

 

[graewulf]

Could the noise you are hearing be In the engine? A bad oil pump could cause your oil light issue.

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[Isaac McShane]

I don't know. It sounds a lot like faulty power steering pump. If it's coming from inside the engine would it sound the same?

Is there a way to test the oil pump?

 

[Isaac McShane]

Also, if the oil pump were going bad wouldn't the engine overheat?

 

[greg92jeepxj]

Hi Issac , welcome to Jeepz.com . If your sure there is no short in the wiring on the oil pressure sending unit switch , is the engine idle stable , not dropping or raising like a vacuum leak at at the correct rpm ? Too low an idle will produce too low oil pressure but would have to be really noticeably low rpm . If you are not getting any rattle , knocking or vibration from the engine , especially under load , rod and main bearings should be ok . As you drive , listen for this.
As far as overheating , knocking would happen before overheating if a bearing(s) were going bad.
Since your curious of your oil pressure , see if you can get a decent oil pressure gauge from a parts store . You want to connect it in line with the existing sending unit so you can get an actual reading in psi so as not to depend on the idiot light. If a really nice one is gotten , you may want to install it on the dash so you may monitor oil pressure as you drive. Since this is troubling you , it may be a good idea to do this. You can't actually test the oil pump itself , you can only check the oil pressure , which is the by-product of the oil pump so that should suffice .
As far as this noise your hearing , try your best to isolate it . An alternator bearing , which the alternator is of course on the opposite side of the power steering pump usually could stand to be checked as well as the a/c compressor . If the a/c clutch bearing is going bad , it may proce a scoring / squealing noise as will an alternator bearing. Also , if this noise is heard at idle and you suspect the steering pump , does it increase when you lean gently on the steering wheel ?
You need to know if any of the driven accessories have a bad bearing before it seizes and throws the serpentine belt. Although the alternator , a/c compressor , power steering pump are important ( also , check the water pump and clutch fan ) , please do get a psi reading for the oil pressure . We know that is important. Wishing you luck and hope all will work out.
P.S. - did you check for a trouble code since the check engine light is on ?
P.S..S- forgot to mention , the o-rings inside the oil filter mount , if they are shrunken , oil pressure is lost there too .

 

[Isaac McShane]

Thanks for the thorough response, Greg!

-The idle is pretty stable, there is no knocking or rattle.

-That's a great suggestion about the oil pressure gauge. I think I'll work on that today.

-The noise definitely seems to be coming from the alternator side, but it seems higher up. It sounds like it's coming directly out of the a/c compressor, No, the noise doesn't really change when the steering wheel is turned, either slightly or rapidly, at idle or while driving. The steering does pretty well, but then again so does the a/c and charging system. But my mechanic buddy is in agreement with me it sounds a lot like a bearing is going bad somewhere on the driven accessories.

The noise is hard to explain. It doesn't sound like squealing so much as a tinnie whine.It's pretty steady.

-The trouble codes are P1698 and P1899.

P1698 is an electrical problem, having to do with the ECU or battery power: P1698 Chrysler ECM Fault No CCD Message From TCM OBDII Engine Light Trouble Code | Engine-Codes.com

It was explained to me that the Jeep was originally an automatic, and after the manual upgrade P1899 has always be on.

-As for the o-rings, I guess if the oil pressure gauge shows low pressure, I'll drop the oil pan and replace the pump and o-rings.

Thanks again for all your information.

 

[Isaac McShane]

I read oil pressure should be anywhere from 10 to 80, with about 30 normal. So, when I hook up the oil pressure gauge, what sort of patterns am i looking for? I would guess that when the oil light comes on the gauge will fluctuate with it.

 

[greg92jeepxj]

Thanks for the thorough response, Greg! -The idle is pretty stable, there is no knocking or rattle. -That's a great suggestion about the oil pressure gauge. I think I'll work on that today. -The noise definitely seems to be coming from the alternator side, but it seems higher up. It sounds like it's coming directly out of the a/c compressor, No, the noise doesn't really change when the steering wheel is turned, either slightly or rapidly, at idle or while driving. The steering does pretty well, but then again so does the a/c and charging system. But my mechanic buddy is in agreement with me it sounds a lot like a bearing is going bad somewhere on the driven accessories. The noise is hard to explain. It doesn't sound like squealing so much as a tinnie whine.It's pretty steady. -The trouble codes are P1698 and P1899. P1698 is an electrical problem, having to do with the ECU or battery power: P1698 Chrysler ECM Fault No CCD Message From TCM OBDII Engine Light Trouble Code | Engine-Codes.com It was explained to me that the Jeep was originally an automatic, and after the manual upgrade P1899 has always be on. -As for the o-rings, I guess if the oil pressure gauge shows low pressure, I'll drop the oil pan and replace the pump and o-rings. Thanks again for all your information.

Hey issac , hope I did not confuse you , think I did . The o-rings I was referring to are in the oil filter housing . There is one bolt that holds it on to the side of the engine block. There should be no need to remove the pan . The bolt that holds the housing on has a hex shaped nut casted to allow a wrench to unbolt it . I never saw one , but heard some have a torx. Check this . As far as the noise , the only other items externally are the a/c clutch and a idler pully that I forgot to mention. Engine oil pressure on my truck '92 4.0 is about 30-40 psi warm but I placed some o-rings that are not spec on the bolt that holds the oil filter mount on . Look for the Fel-pro kit that has all three. Hoping this helps you . Greg
Also , you may be getting those DTC codes since there is probably a difference in PCM from auto to manual . Will have to research that.

 

[Isaac McShane]

Great, thanks Greg. I hooked up the oil pressure gauge today, and it's reading 50-65psi. I didn't drive it more than 10 minutes with the gauge, so maybe it'll drop lower once it's warmer.

I think maybe the sending unit was loose or going bad, and screwing with the idiot light. I've got the pressure gauge mounted so I'll keep an eye on it.

 

[Isaac McShane]

I just got back from 2 hours of pretty serious rock crawling in low gear. She did really well, and had tons of power, maintaining a steady oil pressure around 55psi. On the last stretch before the gravel road I went through some real deep mud holes, and the battery idiot light came on, lights dimmed along with a loud squealing that lasted a few seconds and power steering weekend for a minute, then the steering came back on and the battery light went off.

A minute later I got to the gravel road, took it out of 4low, and started driving up the gravel road, but I had no power. It sounded like it was going to stall in first gear. I ended up rolling down to the bottom of the hill and gaining some momentum to drive up the hill. This wasn't a big hill. I should have been able to drive up it in 2nd gear easy. **While the engine was struggling to make it up the hill, my new oil gauge showed pressure dropped down to 40 and below. It sounded like I was going to stall, and sounded very "clinky".

Once I got to the top of the hill and started picking up momentum I gained power, oil pressure rose back to normal, and the engine sounded good again. It's probably another 2 miles of uphill driving to the highway, and a couple of times I could feel I lost power and had to downshift, then the power would kick back on. This pattern coninitued the few miles it is back to my house. Mainly driving normally, but occasionally losing pressure momentarily.

She preformed so well with tons of power throughout the whole off roading trip, but as soon as I went through the deep mud hole and heard the loud squealing for a few seconds she started acting up. This has happened before when I went through a mud hole. That's got to mean something, right?

 

[greg92jeepxj]

While I'm happy for you that the jeep is basically performing well and that the oil pressure seems fine ( thankfully) , the power loss glitch is unerving. Well, I think that the mud crossing had much to do with it. Anyone who plays in the mud knows that and I'm sure you do to.
My first reaction is that the serpentine belt slipped and caused the alternator to lose tension , therefore not cranking out enough amperage and causing the lights to dim as well as all electrical to suffer . This happened to me in a rain storm recently and I knew my serpentine belt needed adjustment . I don't have an automatic tensioner , I adjust mine with the power steering turn buckle. I lost power as you did and experienced much the same as you did . Now I'm thinking that belt tension is an issue that must be addressed on your machine. My '92 XJ has a manual tensioner with an idler pully , not sure if your '97 has the same set up or did Chrysler install auto tensioner on yours. But belt tension surely ought to be checked. If your engine uses an idler pully too , they wear so it needs to be checked. The idler should spin relatively quiet and smooth with the sepantine belt off to test it and the seal on the back side should not be tone or out of place. They make a racquet if worn , they're of the ball bearing type , usually . Some may be a bushing.
But the belt tensioner may not be holding up as it sounds like your losing power due to alternator not cranking out amps due to belt tension issues. To be sure , watch the belt with the engine at idle and raise the rpms and see if the belt deflects wildly or looks like it may slip off a pully.
Id say start there to see if these issues exist . We all agree in this forum and many would as well to start with the simple inspections like clean battery cables , grounds , check fuel pressure , etc. , it's the general inspections that we are periodically responsible to do that turn up surprises and makes us happy we did check before distaster strikes . Makes us spend money too but hey , that's why they make jeeps , right ? Lol. Your oil pressure seems good and the jeep performs overall well so I would say the serpentine belt tension check should be done .
Once that is completed and if something like a tensioner needs replacement (automatic) or adjustment needed (manual) , then a charging system check to be certain of alternator output is in spec. I got a nice amp clamp from radio shack for this but you can use a good volt meter on the battery terminals too. Check battery volts engine off after jeep sits over nite and then warm it up . Check volts idle and then turn on headlights , defrosters wipers , heavy amperage drawing stuff that will excite the alternator to charge . Voltage regulator picks up load and will do this.
Make this check at about 2000 to 3000 rpm to look for max volt output from alternator. Note at what rpm it planes out at. Not real important to know that but since the engine dosen't always spend time in higher rpm , it's good to know its charging well at normal average rpm .
With manual trans , rpms raise and lower more than an auto but if alternator works well , this shouldn't make much difference. Anyway , best to check these simple checks first , and they're free , just elbow grease , before thinking about throwing parts at it expecting to fix and perform better. Got to know how your current parts are performing. It pays to do a good diagnostic check as you save money ( sometimes costs you money) and find what's right and wrong.
Let us know if all is well and what you find and certainly if you have any questions.
Im not ASE certified , but I got a curbside degree in wrenching and got scars for merit badges. Lol . Trying to stay out of the emergency room is a lifetime occupation alone!

p.s.- took a fast look at the diagnostic code the jeep is throwing and one symptom is transmission controller unit unable to communicate. This makes sense because that is for the former auto trans and not used for the manual . The stock PCM which is service coded for the auto trans is asking for it and not getting a signal . Makes you wonder if this plays havoc on the jeep and causes any glitch such as your experiencing . We'll keep that in mind.
forgot to ask , did you find it necessary to change oil pump ? I know you did not post you did change it , so I'm assuming the pressures your getting are from the same oil pump ?

 

[Isaac McShane]

Thanks again for the all the great info Greg. I, too, enjoy wrenching, and problem solving. I've been doing it practically my whole life, so you think I'd know more!

You are correct in thinking I did not need to change the oil pump. Oil pressure seems sufficient as is.

When I took the serptentine belt off the other day I I tried spinning all the pulleys by hand and they all spun easily. There may have been a slight bit more resistance on the power steering and a/c pulley, but only miniscule differences.

Mine does not have an auto tensioner. There tensioner pulley is under the power steering system. There's a long bolt running through the pulley to adjust the tension. I like that set up. When I put the belt back on, I watched the clean threads go back under the bolt to signify the belt tension is matched to where it has been, then I went ahead and gave it a few more turns just to get her nice and tight.

The belt apprears to be running smoothly with no deflections or slipping. However, I'd be curious to check the belt the next time I loose power. Perhaps then it is off track.

I'll take a look at the electrical system today.

Here's a thought. I keep coming back to the fact that the loss of power occurs after going in a real deep mud hole, and the loud squealing right afterwards. When I took the belt off I inspected it, and it didn't look dry rotted or warped. It seemed in good condition. Could the belt be messed up, even if it appears in tact?

You might have deduced the Jeep is a new purchase of mine. She was actually a Kentucky State Inspector's vehicle for about a decade, (which leads me to believe she had regular maintenance), then a retired state trooper bought her. So I think she's been taken good care of.

 

[greg92jeepxj]

Thanks again for the all the great info Greg. I, too, enjoy wrenching, and problem solving. I've been doing it practically my whole life, so you think I'd know more! You are correct in thinking I did not need to change the oil pump. Oil pressure seems sufficient as is. When I took the serptentine belt off the other day I I tried spinning all the pulleys by hand and they all spun easily. There may have been a slight bit more resistance on the power steering and a/c pulley, but only miniscule differences. Mine does not have an auto tensioner. There tensioner pulley is under the power steering system. There's a long bolt running through the pulley to adjust the tension. I like that set up. When I put the belt back on, I watched the clean threads go back under the bolt to signify the belt tension is matched to where it has been, then I went ahead and gave it a few more turns just to get her nice and tight. The belt apprears to be running smoothly with no deflections or slipping. However, I'd be curious to check the belt the next time I loose power. Perhaps then it is off track. I'll take a look at the electrical system today. Here's a thought. I keep coming back to the fact that the loss of power occurs after going in a real deep mud hole, and the loud squealing right afterwards. When I took the belt off I inspected it, and it didn't look dry rotted or warped. It seemed in good condition. Could the belt be messed up, even if it appears in tact? You might have deduced the Jeep is a new purchase of mine. She was actually a Kentucky State Inspector's vehicle for about a decade, (which leads me to believe she had regular maintenance), then a retired state trooper bought her. So I think she's been taken good care of.

Your welcome for what info I can help you with Isaac. Good that the pulleys are not binding or worn , and I would say that the power steering and a/c clutch pully sounds to be ok . I was surmising you probably had the same belt tensioner as I do , I like this set up as well . No expensive auto tensioner a to buy when worn , the current set up will last forever.
As far as belt tension , I am never satisfied at too tight or too loose so I rotate the engine by hand 720 degrees ( two revolutions ) and check again. Then of course as you said , run it a while a recheck. Never want a belt too tight , bad for accessory bearings and water pump . You know the story with too loose. If your serpentine belt does not appear to have any damage or burned or shredded ribs , should be ok to. Wondering if the mud is getting in between the pullies and belt and causing this screech ?
With muddy water splashing about under the hood , guess that will happen. The XJ cherokee is supposed to have a covering by the radiator support to prevent as best as possible this kind of thing happening . It's sort of like the flexible flaps on some wheel wells found on cars. Mine is missing , is yours too ? Also , did all the spline ribs on each pulley appear to be ok , us damaged ?
No tool marks ? Flattened ribs on these pullies can cause such problems. These little but significant problems will be worked out , but glad you got your hands on a cherry XJ that was well taken care of ! Still,thinking about this dilemma of the belt screech.
Yeah , curious of the alternator readings to but I feel they ought to be ok but always good to check regularly.
Don't want ya stuck out there. I feel jeeps are supposed to be driven under their own power , not pushed , pulled or owed .
Well , that's the general plan anyway . Will be looking for,your post brother . Thanks . Greg

 

[Isaac McShane]

I just drove through the same trail I did on Thursday, and after going through the deep mud holes at the end my power bogged down again, so I took out the volt meter and started checking the power. Power was good, (about 14v), and as I was testing the voltage I was watching the pulleys. When The squealing started and the engine started bogging down the pulley seemed to seize up. The pulley rim where the belt sits continued to spin, but the metal inside would stop spinning and you could see the bolts, then it started again and the squealing stopped. It acted a little rough on the way back to my house, but seemed to improve as I drove it.

It's got to be the a/c pulley on the left side. That's where the noise has been coming from, and unless the inside part of the pulley is supposed to stop spinning it was obviously malfunctioning.

 

[graewulf]

The a/c pulley is supposed to stop and start as needed. There is a clutch in the pulley that only engages the compressor when needed. Are you running the a/c or defroster? Both will trigger the compressor to run.

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[Isaac McShane]

Yes, I realized that was the clutch this morning. I thought I had the blower on without the a/c, but I'm not sure.Back to square one...

 

[greg92jeepxj]

Hey Issac ! Sounds like the air conditioning system is working as far as the high side pressure cut off is doing its job but t also sounds like the compressor clutch bearing is locking up. To change one , according to my shop manual , a 3/4" nut is removed while holding it with a spanner wrench . Guess you'll have to dream up a spanner or try to thread two bolts to keep the clutch from spinning as you break the torque of the nut. It says it loosens clockwise. Then the front plate . Then dig out the key. Then a snap ring. Then of course a puller to remove the clutch. Just something to get it started , I don't think they're on very tight tolerance , just snug like a steering wheel . If the coil is good ( it engages , so I guess its good) you can leave it in place. I believe you'll just be changing the pully because the bearing is bad.

The he next chance you get to go through that mud hole , make certain the a/c is off ( no defrost mode either ) and if there is no issue like you've been having , I guess we found the perpetrator !
dont know off the top of my head what they get for a pully ( don't know which compressor they used either , maybe sanden ?) but I believe you should only need the pully with the bearing already pressed in . That ought to do it. If a belt is too tight , that will prematurely wear any bearing in any accessory ( alternator , compressor, water pump, power steering , you know).
Hope this helps Isaac and I got a shop manual for '92 which ought to cover your '97 to a degree .
i guess give it a shot when you can. Thanks for your posts Issac . Greg

P.S.- when getting the front plate back on , there is an air gap that needs to be adhered to or else the plate will be too close to the pulley . That's what that nut is supposed to be for , to set the air gap. I would think the new pulley should come with directions about this to .

 

[carnuck]

Sounds like the AC compressor is seizing up.

 

[Isaac McShane]

I haven't had a chance to go through mud holes again (maybe tonight), but I just finished a basic tune up, and afterwards I cranked her up with the a/c and blower off.

Oil psi was about 60, and after a couple minutes I turned the a/c and blower on. There was immediately a squeal from the compressor, and oil pressure dropped to about 54psi. After about 10-20 seconds the squealing stopped.

 

[greg92jeepxj]

Hey Issac . I'll respect what carnuck said since I already went through this on my '92 with pep boys . Too much to get into with my problem then ( all is fine now) and this thread isn't about me anyway so it's definately worth looking for a potential compressor seizure . We don't know if someone charged the system and not enough PAG was put back if there was a major leak or if there was a compressor swap at some point. I will say I saw the paint burned off the new pulley on the rebuilt compressor on my XJ when it was locking up and just about stalling the engine.
Sounds familiar , dosen't it ? That's what I get for letting a station that I was told to trust charge it. Got another compressor and flushed , vac'd and charged it myself. Three years , no problems.
engine off , try turning the hub and see how it feels . Even under pressure , shouldn't be too hard to turn. Just has to turn smooth , but you'll feel compression. If it's tough , then price a rebuilt. If you need any advice on a/c , I can help , I believe mr. carnuck got your back to. The man has 10-w30 in his veins. A vacuum pump is a great investment ( used mine about a dozen times in three years) but if you don't think it'll get much use , even harbor freights price will pay for a evacuation and recharge. Probably best to flush the system , chase with compressed air and swap an accumulator. Then let the a/c man finish it. Make sure they vac , charge it with the right amount of oil , not like they did to me! Let's not get ahead of ourselves , I'm already doing that enough for the both of us. Hoping for the best . Greg