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You are in the Jeep Cherokee and Jeep Grand Cherokee
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Jeep Grand Cherokee, Jeep Grand Cherokee SRT-8, Jeep Cherokee, Engine, SUV
#670 of 731 1998 Jeep Cherokee Oil Pressure Drop
Sep 07, 2011 (7:53 am)
About a month ago, I purchased a 1998 Jeep Cherokee. I took it for a test drive and drove it on the street and also took it out on the freeway. Everything seemed to be working just fine on the vehicle. I checked the oil and it seemed fine and though the engine looked a bit dirty, I felt comfortable with the purchase. I gave the guy the money and drove the vehicle home. The drive home was about 20 minutes and about a block away from my house I had to stop at a stop light. Suddenly I saw the oil pressure drop to 0. I suddenly felt like I had been taken, but I still went home and purchased my insurance to make sure I had the vehicle covered. Not feeling great about my purchase, the one thing that has been keeping me going is that I know the Inline 6 cylinder 4.0 engine is one of the best engines any American car company has ever put into production. So, I thought that a full tune up and an oil and filter change would do the trick. I called a mechanic I trust, and scheduled the appointment for the following Saturday to have the tune up and oil and filter change done. I took the Jeep Cherokee in and my mechanic did a full tune up and the oil an filter change. I picked up the vehicle the next day, and I took my Jeep out for a drive. I drove for about 30 minutes and then had to stop at that same stop light, and of course the oil pressure dropped again though close to 0 but not all the way. I parked the car and did a bit of research online. I found out that a lot of people are having the same issue with their Jeep Inline 6 4.0 engine also. The first thing I did was change the Oil Pressure Sending Unit. This unit sends the information to your pressure gauge in your dash. Apparently they can be faulty as they can be hit or knocked out of place because they stick out slightly from the engine. So, I purchased one for $40, and things seemed to be fine again, but again it was only for about a half hour. The oil pressure dropped again! So on Thursday, I called my mechanic and explained the situation to him. I told him that I changed the Oil Pressure Sending Unit but it did not seem to work. He said that something has got to be blocking the oil from getting to my engine, so we decided to do an engine flush to see if that would get any sludge out of the engine that may be blocking the oil from coming into the engine. So, the oil flush was done on Saturday, and again on Sunday I picked up my car. I drove the car for about 2 days before the engine's oil pressure dropped again, and of course it was at a stop light. So, this is where things currently are for me. I have spoke to my mechanic and also another mechanic who specializes in Jeeps. They both seem to think that it could be the oil pump, but before I spend the $650.00 I have been quoted on the repair, I have decided to take a look at the oil pressure before it goes to the engine. In order to do this, I am purchasing a Mechanic Oil Pressure gauge, pulling the Oil Pressure Sending unit off, inserting the Oil Pressure Gauge, and testing to see if the measurements are within the specs that are in the owners manual. This will be happening on 9/11/11. I have been doing a bit more research on this problem and I have heard that it could be the oil filter is not compatible with my engine and that a Napa Gold oil filter worked for others. The Mechanic Oil Pressure gauge will tell me what the pressure is before the oil is pumped through the the filter and through the engine. If the pressure is low before the oil is pumped through the filter and into the engine, then I know the problem is the oil pump. If the pressure is fine before the oil is pumped through the filter and into the engine, then I know there is some loss of pressure in the engine. So, this is where things currently stand. If anyone else can think of anything that might help, please let me know. I will be watching for updates.
#671 of 731 Re: 1998 Jeep Cherokee Oil Pressure Drop [98cherokeeken]
Sep 07, 2011 (10:50 am)
I have a 1994 JGC with the same engine. It has nearly 300,000 miles on the original engine. My oil pressure gauge goes from 0 - 80 at any given time with no apparent reason. Instead of relying on the gauge I rely on the performance of the engine. Oil and filter changes every 3500 miles and everything has been fine since I bought my Jeep 15 years ago. My mechanic tells me its as strong now as its ever been.
#672 of 731 Re: 1998 Jeep Cherokee Oil Pressure Drop [b_web]
Sep 07, 2011 (2:12 pm)
9/11/11 is a good day to commit to a jihad on our crappy trucks that we repair and repair and repair. I would like to listen to my gps calmly saying "recalculating" as it plunges to its death at a local cliff. I will never buy an american car again. Sad. :+( BTW, if your Jeep product is red, you can call it a "crimson jihad".
No I am not trying to make fun of the sad events at 9/11, but only to poke fun at a vehicle that J have poured thousands of dollars into.
#673 of 731 Engine trouble? -1996 Jeep Grand Cherokee Limited
Sep 07, 2011 (7:18 pm)
I am not car savvy at all. My Jeep is an automatic... I've been having some problems- staling when I back up, some slack in shifting, and possibly misfiring of the spark plugs. I took it in for a mechanic (friend of a friend) to do an electrical check of some kind (free). He said about 4 spark plugs were misfiring. He told me he could run a check on the whole engine ($75) but the spark plugs probably needed to be changed. Trying to save a little money, I bought the spark plugs and my ex and oldest son offered to do it for me. They had no clue what they were doing either. So, they removed all the wires on one side at once before they realized they were supposed to do it one at a time. They said all the wires on that side seemed to be in the wrong place (according to the diagram). They replaced all the plugs and it wouldn't crank. Then they put new wires and a new distributor cap cord on. It still won't crank. I'm concerned that it's something more serious. But, before they worked on it, it would crank. Could there be an alternative firing order for the cords to the spark plugs? That's what we keep wondering, because they said the old cords were in a different order when it was running. We really need help! I can't afford to take it in!
#674 of 731 4 plugs gone bad....
Sep 09, 2011 (3:18 am)
You have got to take it in. The reason your plugs are not firing is due to an ignition or computer issue. 4 plugs do not go bad all at once. The plugs are a symptom of a greater electrical issue.
#675 of 731 Re: 2011 Hemi hesitation/misfire problem [deeceesd]
Sep 28, 2011 (10:46 am)
deeceesd. Thanks for the posts. I'm having the same issue as you described on my '11 GC 5.7L. I have not taken it to the dealer yet. I'm at approximately 3,000 miles. Curious of the fix if you ever got a resolution from Chrysler? I too was questioning the locking torque converter.
#676 of 731 Re: 2011 Hemi hesitation/misfire problem [burbo7]
Sep 30, 2011 (7:19 am)
I am sorry your Grand Cherokee is deceased. Are there funeral Arrangements? Possibly a viewing? Or is it so horribly messed up that it is a closed repair bay service? LOL.
I still love my Grand Cherokee, especially the music of the V8. however, never a day goes by that I do not regret buying it and sinking 10,000.00 in repairs over the past 5 years. It has been difficult. Every repair I have had is over $2000.00.
I will not buy one again. It was just too much. I am gun-shy of Chrysler forever!
#677 of 731 Re: 1994 Grand Cherokee dying while driving [guertin]
Oct 14, 2011 (7:27 pm)
Well first things first...you want to start with the most basic, most importantly, cheapest things first. (I just realized how old this post is...lol...still) If the fuel pump goes out it won't crank at all...you can turn the key to the ON position just before trying to start it. You should hear the fuel pump kick on for just a sec or two at the rear of the vehicle (it is at the top of the gas tank). In the fuel system I would start with the fuel filter first. People would be amazed to know the types of problems which can be caused by not keeping up with regular maintenance of a vehicle (changing the oil and oil filter, changing the fuel filter, changing the spark plugs and spark plug wires, chainging the air filter.) I had a 1994 Jeep Grand Cherokee with the inline 6 cylinder engine. Very simple cars to work on. Its system does not have things such as a throttle adjustment screw...if it is not idling or running correctly start with these minor things first (according to the symptoms of the issue you are having...starting system, etc...). You have to drop the gas tank to get to the fuel pump on these vehicles...its not that difficult but a new one does cost about $300. Had to do this on mine while I owned it. These tips can be used with almost all vehicles...they are all very similar. Except for CHRYSLER!!!! Steer clear of those!!!! lol. My wife owns a 97 Sebring and it has given me and all mechanics I know more problems than any vehicle.
#678 of 731 Re: 1994 Grand Cherokee dying while driving [mechman86]
Nov 01, 2011 (9:42 am)
my 1996 gc laredo w 218.000 miles has been dying while driving or coming to a stop. The oil pressure dropped to zero just before. No "check engine light". I could restart it immediately dropping into neutral while coasting along. this worked good on freeways but it's stressful to say the least. Have had my mechanic replace coolant sensor, temp sensor, crank position sensor & new battery & belt. Display kept showing "bad coolant sensor. Then it wouldn't start. Finally took it to jeep dealer who replaced plugs & wires, cleaned distributor, new gasket on valve cover for $700. Said they wouldn't reset the computer module. After driving it for 4 hours and about 300 miles running just great it up and dies again, once when stopping, then when underway. Jeep dealer says it needs a new PCM & ignition coil for another $1000. Hate give up this car as it goes anywhere and is a joy to drive, but is it worth it now? Anyone with any more ideas?
#679 of 731 Jeep dying
Nov 01, 2011 (11:21 am)
I just went through this with my 94 JGC. I did all the same things you did. It did end up being the PCM. Once the PCM was replaced for $500 I have had no issues. When you think about it, it makes sense. It is a very old computer, how long is it supposed to last. Mine was in bad shape when they pulled it off. It also corrected my hard starting problem. Good luck.