Jeep kj oil leak/10.5 mpg?

Eric120daniel

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Jeep Kj nightmare.


Hi, this will be my first post here as I’ve been stuck with a few problems on my Liberty and can’t find any information retaining to my specific situation. I have a 2003 3.7 v6 jeep liberty close to 170,000 miles. Ever since I got the Jeep close to three years ago it's always leaked oil from the valve covers. When it got to the point where the dipstick had no oil on repeatedly when I checked my oil I decided to tackle my first mechanic repair. I changed the valve cover gaskets out. The oil level started slowly getting low and eventually, I noticed there was smoke coming off the exhaust. It was still leaking oil from the passenger's side valve cover come to find out I had stripped out (or the hot leaking oil had destroyed) the very back bottom bolt threads. Tried to helicoil it and failed because I couldn’t get a straight angle due to the firewall. After trying and failing repeatedly by heliox coiling the threads and then replacing the gasket again then completely going ghetto and getting a longer bolt and nut then running the bolt through the head because there was a hole on the other side then attaching the nut which killed me inside it still leaked and I gave up. Especially when I found out the previous owner had replaced the valve cover gaskets only two years before I had got the car. I've been driving around breathing in burning oil fumes and trying to ignore the huge cloud of smoke that comes from under the hood anytime I parked. My friend was recently giving me **** about it and even though I had become oblivious to it I did want to fix it as I had just done new upper and lower ball joints as well as shocks and struts and I put rear brakes on it before that. I admit it was dumb to not fix the oil leak before fixing other stuff but at that point, I had just given up and become oblivious to it as I said.

Researching the topic I only found one forum which talked about my original suspicion that maybe the valve covers themselves were warped ( the driver's side had started leaking again recently) but there was never any fix to the problem in the forms. I was going to go to my local junkyard and get a pair of valve covers off another liberty but something about one of the comments stuck in my head. The comment asked if the oil was pooled at the top of the heads when the person had done valve cover gaskets and I remembered every time I took the valve covers on mine off there was a huge pool of oil. His comment also mentioned the PCV which afterward I learned how important a PCV valve was. I had originally replaced the PCV valve the first time I did valve cover gaskets but the hose that connected it ripped ( I didn’t know the twist method yet lol) and I had replaced it with an AutoZone “PCV OEM” hose. I went to go check if the valve had vacuum so I had the car running and before I even got the oil cap off I noticed the hose I had replaced was completely collapsed which wasn’t the case when the engine was off. I pinched it to get it to open and felt the extreme amount of pressure running through the hose. Shut the car off, grabbed a pack of zip ties, and made it so the zip ties support the hose not allowing it to collapse. Immediately the jeep sounded better after this and I hadn’t even noticed it wasn’t running well before. The car always shook badly at idle although it wasn’t misfiring and it was much better with the zip tie fix.

My theory was that because the gasses were not getting properly vented from the PCV pressure was building up forcing oil that wasn’t draining in the heads out of the valve cover gaskets therefore that's why I could never get rid of the oil leak. I don’t know if it worked or not because right after this event I found out my coolant reservoir has cracked and has been leaking onto the same valve cover and therefore onto the exhaust still causing the car to smoke. I was also excited because I figured the PCV valve being fixed would now get me better mpg since I’m not doing so amazing financially and gas has become horribly priced. I calculated my mpg and I got 10.5! I’ve never calculated it before but I fill the car every week at half a tank and it's always around 5 gallons. I ran the numbers 5 times and it was still 10.5. I have no errors in my math I’m sure. With city being 16 even if I have a led foot I should be getting around 12 or 13 right? This is my breaking point as someone who loves my liberty but wants something more preformance based if I’m paying the same price for gas as I would in a v8 why should I keep farting with liberty when it's not in any way a performance car?

I guess what I’m asking is people's experience/ opinions on the matter because I do really like my liberty and wanted to use it as a daily for as long as I could. It also was a gift but I don’t want to keep chasing this issue. Especially if the mpg is so horrible. Should I list it on marketplace and buy something else? Am I overlooking something stupidly simple? Is there an issue that is causing all of my issues?

Things to note
The muffler is rotted out. I'm not sure about the rest of the exhaust. I'm going to inspect it asap. Never really cared as almost everyone where I live has a messed up exhaust. I’ve just learned that can affect mpg
No idea if it's still leaking oil. I will patch the coolant reservoir asap and get back to this form once I know for sure.
NO check engine light has ever been on except for an 02 sensor that was unplugged( IDK how it happened) it hasn’t been on for a few months
Has a clean air filter and airbox
Did plugs on it about two years ago
Have a lead foot but this week I’m gonna back off and see if it makes a difference.
Oil’s good, diff fluid is good, transmission fluid is good and transfer case fluid is good.
PCV hose is still zipped tied but has a good vacuum. Not going to buy a new hose till I’m sure what the mpg deal is.
Everything on the car is stock including tires and rims besides an amp connected to a sub and rear doors
All injectors are original, might take out and clean if I’m feeling motivated or not.
Might also clean the throttle body and butterflies.
I always run it up to temp
I do mostly city driving but do drive on the highway for my weekend job
I don't keep it running while I sit in it nor start it to let it warm up.

I appreciate any opinions and recommendations. Will give updated info as soon as I can.
 

Eric120daniel

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Update not sure if this helps.
Coolant tank is patched wiped all coolant and oil away and will look for leaks.
My friend gave me some injection cleaner he had left over so I put it in my tank earlier today. My tank is close to full so I know your supposed to use it when you fill but I didn’t feel like getting three dollars worth of gas. I’m gonna drive with overdrive off for this week too so hopefully the higher rpms will clean out some of the carbon and injectors.
I forgot to say I made sure all my valve cover bolts where tight as well.
Will update once I have more information.
Also almost forgot just had a CEL pop up when I was driving. Once I get home I’ll scan it and see what it’s about but haven’t noticed anything immediately wrong.
 

JRB

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Seems like a bunch of small problems to chase and you'll hopefully have it back up and running in reasonable shape.

As far as mpg's, they'll at least be a few more than the 10 you're getting once its running better. You said the plugs haven't been changed in a couple years, after taking care of any of the small pcv and other little things, get some new copper plugs in there. Keep in mind while its running rough/rich they'll foul out quicker, so chasing the little things of pcv and hoses that are bad will be better to do sooner than later.

Other little basic things too, make sure your air filter is clean, any sensors, flow, throttle, temp, make sure to clean them with an approved cleaner for the delicate electronics.

It can be discouraging when vehicles can give ya a bunch of ****, and ultimately trying to get it best shape it can be in will be beneficial whether you decide to keep or sell. Checking it out to see what that code was, and the other visual inspections will hope you get more of an assessment of it.
 

Eric120daniel

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Seems like a bunch of small problems to chase and you'll hopefully have it back up and running in reasonable shape.

As far as mpg's, they'll at least be a few more than the 10 you're getting once its running better. You said the plugs haven't been changed in a couple years, after taking care of any of the small pcv and other little things, get some new copper plugs in there. Keep in mind while its running rough/rich they'll foul out quicker, so chasing the little things of pcv and hoses that are bad will be better to do sooner than later.

Other little basic things too, make sure your air filter is clean, any sensors, flow, throttle, temp, make sure to clean them with an approved cleaner for the delicate electronics.

It can be discouraging when vehicles can give ya a bunch of ****, and ultimately trying to get it best shape it can be in will be beneficial whether you decide to keep or sell. Checking it out to see what that code was, and the other visual inspections will hope you get more of an assessment of it.
It was a 303 multiple misfires on cylinder 3. I was like no big deal because that was the one I though the coolant tank was dumping coolant onto so I’ll just clean the connector but it’s on the drivers side so I was wrong. I changed the plugs out two years ago. They calmed they where pre gapped but I’m going to try and get it into my college shop tomorrow because I don’t have a feeler gage at my house. If all the plugs are good then I’ll test the ignition coils and if there good then I don’t know I’ve heard there’s a relay that all ignition coils are connected too but besides that I think the coils are hooked directly up too the ecu? I didn’t really think about it but if the pcv has been off all this time the plugs might be covered in carbon or unburnt fuel. I’ve been hearing a lot of good things about copper plugs lately so I’ll definitely give them a shot if I do need to replace them. I checked my air box and filter last night. I’m gonna pull the entire intake off and inspect my throttle if I get it into the shop tomorrow because I never can have car issues when it’s warm outside lol.

I mean I really do like my kj the visibility is amazing and right now I really can’t afford another car nor do I really want to get rid of it. I’ve just been fighting with it for so long and it seems like all my friends in my auto class have multiple cars somewhat performance based so it does get frustrating that I can’t really afford anything but although I’m fighting all these issues it has never left me stranded it is a really awesome Jeep. I still want to someday get wheels on it and maybe even a lift if the shocks and struts I put in wear down. I’m gonna do my best to fix it like I said if I can get better mpg I need to replace the pcv hose and coolant tank again. Also I might need to do valve cover gaskets for like the millionth time on it but it’s not that bad since I’ve already done it. It’s just finding out why it’s so bad that I’m having trouble with because I can spend my money on new injectors and it could be the rotten exhaust, plugs and ignition coils, something completely unrelated so idk.
 

Eric120daniel

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It was a 303 multiple misfires on cylinder 3. I was like no big deal because that was the one I though the coolant tank was dumping coolant onto so I’ll just clean the connector but it’s on the drivers side so I was wrong. I changed the plugs out two years ago. They calmed they where pre gapped but I’m going to try and get it into my college shop tomorrow because I don’t have a feeler gage at my house. If all the plugs are good then I’ll test the ignition coils and if there good then I don’t know I’ve heard there’s a relay that all ignition coils are connected too but besides that I think the coils are hooked directly up too the ecu? I didn’t really think about it but if the pcv has been off all this time the plugs might be covered in carbon or unburnt fuel. I’ve been hearing a lot of good things about copper plugs lately so I’ll definitely give them a shot if I do need to replace them. I checked my air box and filter last night. I’m gonna pull the entire intake off and inspect my throttle if I get it into the shop tomorrow because I never can have car issues when it’s warm outside lol.

I mean I really do like my kj the visibility is amazing and right now I really can’t afford another car nor do I really want to get rid of it. I’ve just been fighting with it for so long and it seems like all my friends in my auto class have multiple cars somewhat performance based so it does get frustrating that I can’t really afford anything but although I’m fighting all these issues it has never left me stranded it is a really awesome Jeep. I still want to someday get wheels on it and maybe even a lift if the shocks and struts I put in wear down. I’m gonna do my best to fix it like I said if I can get better mpg I need to replace the pcv hose and coolant tank again. Also I might need to do valve cover gaskets for like the millionth time on it but it’s not that bad since I’ve already done it. It’s just finding out why it’s so bad that I’m having trouble with because I can spend my money on new injectors and it could be the rotten exhaust, plugs and ignition coils, something completely unrelated so idk.
Also almost forgot again I cleared the misfire code and it hasn’t reset yet. I’ve been driving it all day and it’s been ok.

Another update my blower motor no longer functions. It’s not the end of the world as my a/c has never worked but I’ll need to fix it before next winter. I guess the Libertys mad at me lol.
 
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klc

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Your blower motor might not be working because the resistor pack is kaput. This thread helped me fix mine after the two low speeds went out.
 

Eric120daniel

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Your blower motor might not be working because the resistor pack is kaput. This thread helped me fix mine after the two low speeds went out.

Yeah I replaced the resistor a few months back with a dorman product because I had the same problem. I’ve heard bad things about them so idk if I have it or not but if I kept the old resistor I’ll swap em out and see if the blowers bad. It’s made a few concerning nosies so it’s probably the blower that went out.
 
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klc

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Yeah I replaced the resistor a few months back with a dorman product because I had the same problem. I’ve heard bad things about them so idk if I have it or not but if I kept the old resistor I’ll swap em out and see if the blowers bad. It’s made a few concerning nosies so it’s probably the blower that went out.
Okay, noises are often bad in this context.
 

Eric120daniel

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Okay, noises are often bad in this context.

Yeah it’s what is. Luckily I don’t desperately need it as of now. It’s cold but not in the negatives anymore and I fixed all my windows because the a/c never worked
 
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fbjernee

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Jeep Kj nightmare.


Hi, this will be my first post here as I’ve been stuck with a few problems on my Liberty and can’t find any information retaining to my specific situation. I have a 2003 3.7 v6 jeep liberty close to 170,000 miles. Ever since I got the Jeep close to three years ago it's always leaked oil from the valve covers. When it got to the point where the dipstick had no oil on repeatedly when I checked my oil I decided to tackle my first mechanic repair. I changed the valve cover gaskets out. The oil level started slowly getting low and eventually, I noticed there was smoke coming off the exhaust. It was still leaking oil from the passenger's side valve cover come to find out I had stripped out (or the hot leaking oil had destroyed) the very back bottom bolt threads. Tried to helicoil it and failed because I couldn’t get a straight angle due to the firewall. After trying and failing repeatedly by heliox coiling the threads and then replacing the gasket again then completely going ghetto and getting a longer bolt and nut then running the bolt through the head because there was a hole on the other side then attaching the nut which killed me inside it still leaked and I gave up. Especially when I found out the previous owner had replaced the valve cover gaskets only two years before I had got the car. I've been driving around breathing in burning oil fumes and trying to ignore the huge cloud of smoke that comes from under the hood anytime I parked. My friend was recently giving me **** about it and even though I had become oblivious to it I did want to fix it as I had just done new upper and lower ball joints as well as shocks and struts and I put rear brakes on it before that. I admit it was dumb to not fix the oil leak before fixing other stuff but at that point, I had just given up and become oblivious to it as I said.

Researching the topic I only found one forum which talked about my original suspicion that maybe the valve covers themselves were warped ( the driver's side had started leaking again recently) but there was never any fix to the problem in the forms. I was going to go to my local junkyard and get a pair of valve covers off another liberty but something about one of the comments stuck in my head. The comment asked if the oil was pooled at the top of the heads when the person had done valve cover gaskets and I remembered every time I took the valve covers on mine off there was a huge pool of oil. His comment also mentioned the PCV which afterward I learned how important a PCV valve was. I had originally replaced the PCV valve the first time I did valve cover gaskets but the hose that connected it ripped ( I didn’t know the twist method yet lol) and I had replaced it with an AutoZone “PCV OEM” hose. I went to go check if the valve had vacuum so I had the car running and before I even got the oil cap off I noticed the hose I had replaced was completely collapsed which wasn’t the case when the engine was off. I pinched it to get it to open and felt the extreme amount of pressure running through the hose. Shut the car off, grabbed a pack of zip ties, and made it so the zip ties support the hose not allowing it to collapse. Immediately the jeep sounded better after this and I hadn’t even noticed it wasn’t running well before. The car always shook badly at idle although it wasn’t misfiring and it was much better with the zip tie fix.

My theory was that because the gasses were not getting properly vented from the PCV pressure was building up forcing oil that wasn’t draining in the heads out of the valve cover gaskets therefore that's why I could never get rid of the oil leak. I don’t know if it worked or not because right after this event I found out my coolant reservoir has cracked and has been leaking onto the same valve cover and therefore onto the exhaust still causing the car to smoke. I was also excited because I figured the PCV valve being fixed would now get me better mpg since I’m not doing so amazing financially and gas has become horribly priced. I calculated my mpg and I got 10.5! I’ve never calculated it before but I fill the car every week at half a tank and it's always around 5 gallons. I ran the numbers 5 times and it was still 10.5. I have no errors in my math I’m sure. With city being 16 even if I have a led foot I should be getting around 12 or 13 right? This is my breaking point as someone who loves my liberty but wants something more preformance based if I’m paying the same price for gas as I would in a v8 why should I keep farting with liberty when it's not in any way a performance car?

I guess what I’m asking is people's experience/ opinions on the matter because I do really like my liberty and wanted to use it as a daily for as long as I could. It also was a gift but I don’t want to keep chasing this issue. Especially if the mpg is so horrible. Should I list it on marketplace and buy something else? Am I overlooking something stupidly simple? Is there an issue that is causing all of my issues?

Things to note
The muffler is rotted out. I'm not sure about the rest of the exhaust. I'm going to inspect it asap. Never really cared as almost everyone where I live has a messed up exhaust. I’ve just learned that can affect mpg
No idea if it's still leaking oil. I will patch the coolant reservoir asap and get back to this form once I know for sure.
NO check engine light has ever been on except for an 02 sensor that was unplugged( IDK how it happened) it hasn’t been on for a few months
Has a clean air filter and airbox
Did plugs on it about two years ago
Have a lead foot but this week I’m gonna back off and see if it makes a difference.
Oil’s good, diff fluid is good, transmission fluid is good and transfer case fluid is good.
PCV hose is still zipped tied but has a good vacuum. Not going to buy a new hose till I’m sure what the mpg deal is.
Everything on the car is stock including tires and rims besides an amp connected to a sub and rear doors
All injectors are original, might take out and clean if I’m feeling motivated or not.
Might also clean the throttle body and butterflies.
I always run it up to temp
I do mostly city driving but do drive on the highway for my weekend job
I don't keep it running while I sit in it nor start it to let it warm up.

I appreciate any opinions and recommendations. Will give updated info as soon as I can.
Check the Egr Tube out, i managed to double my fuel economy after discovering a hole in the egr tube under the thermal wrap, i dont know how it happened or got there but its worth looking, Also as bad as your fuel economy is, keep in mind even in optimal condition the 3.7 engine is about as economic on fuel as a 4.7, On a highway you might see 20-25 mpg but in town youre going to be doing maybe 15, Hope This Helps!
 

Eric120daniel

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Check the Egr Tube out, i managed to double my fuel economy after discovering a hole in the egr tube under the thermal wrap, i dont know how it happened or got there but its worth looking, Also as bad as your fuel economy is, keep in mind even in optimal condition the 3.7 engine is about as economic on fuel as a 4.7, On a highway you might see 20-25 mpg but in town youre going to be doing maybe 15, Hope This Helps!
I think I fixed the issue lol I’m getting about 13 mpg now so I’m sure that’s accurate with my driving. So where is the egr tube located? I have a 03 I don’t have a mass airflow sensor or really anything on my intake so I’m wanting to take a look at it but wondering if I have one. What year is your KJ?

Thank you for your help.
 
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