New to me Jeep, came with some problems

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Jerrad10

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Texas
Hey guys, purchased a Jeep over the weekend and looking for some help. I knew going into it, that there were going to be a few issues that would need to be taken care of but figured the price was right.

The major problem I am running into right now is the overheating issue. The overheating seems to occur regardless of whether or not I am driving it, or letting it sit idle. Also, the heat/air does not seem to have an effect on it either, it will begin to overheat whether the AC is on, heat is on, or if the entire HVAC system is off.

I did attempt to drive it to work this morning, just to see how bad it got within a 6 mile drive, and it did not go well. I ended up stopping twice on the way to let it cool off as the temp gauge got into the red.

The first time I pulled over I noticed two things. One, I had lost break pressure, which I do not know how or if this is related. Two, there was excessive smoke bellowing out from under the hood.

For further info, this is a 2012 Unlimited Sport with a 3.6L and automatic transmission.

I guess my main question is where to start with the troubleshooting. Appreciate any feedback I can get from you guys
 
It's possible that it has air in the cooling system, raise the front of Jeep up at least 6" with cap off and idling.

Is the cooling fan working, and going into high speed when the temps are hot?
 
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I will check on the engine fan this evening. I do know that the first time I let it sit idling in the driveway that they kicked on but I was not paying attention to the point that they kicked on, or if they started blowing harder at one point vs. another
 
Any audible/loud ticking from the engine?

If you are standing by the engine compartment while it's idling and you hear an obnoxious tick... That's a sure sign of valve seat recession, which was a common issue with that model year vehicle. Valve seat recession can have detrimental effects on cooling if it has progressed far enough.
 
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So I haven't necessarily gotten to a point to where I can burp the system. Without the brakes, I am unable to get it somewhere to lift the front end or get it on an incline.

I did however take the radiator cap off, filled the radiator to the brim with coolant, and make sure that the overflow reservoir had coolant in it as well. With the cap off I started the engine, turned the heat on and went back and forth between watching the temp gauge and watching the coolant level.

While doing so the coolant seemed to steadily seep out of the top of the radiator. The level did drop down once but then came right back up and poured out of the top again. The temp never got past the halfway point on the gauge, and the air coming from the heater never really got warm. I let it run like this for probably 10-15 minutes.

While I had it running I reinstalled the radiator cap, then watched the temp steadily rise. The radiator fans didn't kick on until the temp gauge was at approximately 3/4 but it steadily got warmer. Once the the gauge was between 3/4 and red, the fans kicked into high but again, it kept climbing, and I finally shut it down.

Last thing I noticed was while checking the coolant lines coming from and going to the radiator after I shut it down the line coming into the bottom was definitely hot to the touch but the top line coming out of the radiator wasn't hot at all.
 
You don’t need to drive it anywhere to raise the front end, can simply use a floor jack if needed. It would be easier to monitor the temps with an app such as JScan and a BT OBDII adapter. Entire setup cost about $50 and is well worth the cost.

Be advised there are two coolants, OAT and HOAT, if they are mixed the coolant will sort of “gel” and not function properly. Since you got it used can’t be sure with the PO did with it.
 
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tJKrider said:
Any audible/loud ticking from the engine?

If you are standing by the engine compartment while it's idling and you hear an obnoxious tick... That's a sure sign of valve seat recession, which was a common issue with that model year vehicle. Valve seat recession can have detrimental effects on cooling if it has progressed far enough.
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Thankfully, no ticking at all
Danarch said:
You don’t need to drive it anywhere to raise the front end, can simply use a floor jack if needed. It would be easier to monitor the temps with an app such as JScan and a BT OBDII adapter. Entire setup cost about $50 and is well worth the cost.

Be advised there are two coolants, OAT and HOAT, if they are mixed the coolant will sort of “gel” and not function properly. Since you got it used can’t be sure with the PO did with it.
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I understand, it was still sitting in the parking lot at work yesterday evening. I did get it trailered over to the shop last night and will attempt to burp the system this evening.

I went to the local parts store to grab coolant last night and asked for coolant based off of my year model Jeep. They gave me a yellow 50/50 universal antifreeze. Will this work, or cause further issues?
 
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Jerrad10 said:
Thankfully, no ticking at all


I understand, it was still sitting in the parking lot at work yesterday evening. I did get it trailered over to the shop last night and will attempt to burp the system this evening.

I went to the local parts store to grab coolant last night and asked for coolant based off of my year model Jeep. They gave me a yellow 50/50 universal antifreeze. Will this work, or cause further issues?
Click to expand...
I use only universal. I don't think it's as good as the specific stuff, but it's not far off and it's tons better than mixing.

So has the air coming out of the vents been warm or hot when you turn on the heat? If it's not getting up to temp, then the first thing I would do is replace the thermostat, cheap and easy, and potentially the problem. Do this before you bother burping the system.
 
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Jerrad10 said:
Thankfully, no ticking at all


I understand, it was still sitting in the parking lot at work yesterday evening. I did get it trailered over to the shop last night and will attempt to burp the system this evening.

I went to the local parts store to grab coolant last night and asked for coolant based off of my year model Jeep. They gave me a yellow 50/50 universal antifreeze. Will this work, or cause further issues?
Click to expand...
The wife’s had a bad t-state and it was under warranty so had the shop we use do the work. They flushed the system and said they put universal coolant in it. About 11 months later it started acting up again so messed around with it myself and used the universal coolant for top off etc. Haven’t had any problems. The end issue ended up being another bad t-state which the shop replaced no charge.
 
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I bought an exceptionally clean, high-mileage 2015, that had been babied… driven, but taken care of.
Since then I’ve been constantly throwing money and wrenches at it to keep it running.
By far, the least reliable vehicle I have ever owned, and that’s a pretty big list.
Good luck with whatever you choose to do.
 
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Last night I got some time in the shop with the jeep. I went ahead and swapped out the thermostat, and burped the system. For the first time I actually got to see the engine start to get warm and cool back down, so that is a win so far.

I still believe the true test will be driving it and seeing how it does but I am in the middle of addressing the brake issue now
 
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Well good news guys. I was able to get the brakes fixed Friday afternoon. Had to replace the front right rotor & caliper, as well as pads on both front wheel ends.

Once that was done I got to do some driving to make sure the overheating issue was resolved. I put about 100 miles on the Jeep throughout the weekend without any issue there whatsoever.

The next problem I will be tackling is the intermittent issue I am having with the traction control light coming on. I have read up on this a little and signs point to an ABS wire or wheel speed sensor issue. The one thing that confuses me a little is that even though the traction light comes on, the ABS light does not.

Any suggestions here?
 
Jerrad10 said:
Well good news guys. I was able to get the brakes fixed Friday afternoon. Had to replace the front right rotor & caliper, as well as pads on both front wheel ends.

Once that was done I got to do some driving to make sure the overheating issue was resolved. I put about 100 miles on the Jeep throughout the weekend without any issue there whatsoever.

The next problem I will be tackling is the intermittent issue I am having with the traction control light coming on. I have read up on this a little and signs point to an ABS wire or wheel speed sensor issue. The one thing that confuses me a little is that even though the traction light comes on, the ABS light does not.

Any suggestions here?
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Is your steering wheel straight when driving straight down the road?

Do you have any play in your steering when driving straight down the road?
 
Steering wheel seems to be straight to me, and I do not notice a lot of play, at least until the traction light comes on. At that point I do notice play in the steering. I will pay more attention to this on the way home this afternoon though
 
Jerrad10 said:
Steering wheel seems to be straight to me, and I do not notice a lot of play, at least until the traction light comes on. At that point I do notice play in the steering. I will pay more attention to this on the way home this afternoon though
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If your steering wheel isn't centered or your having to move it back and forth alot to keep going straight then it will set off your traction control.
 
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Jerrad10 said:
It has a 2.5" Rough Country lift
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You might want to also check the front axle to make sure it's sitting in the center of the Jeep. Use a 4' level against the tires if they stick past the fenders or set level so it's straight up and down against the fenders. Then measure either from the fenders to the tire or the tire to the fender on both sides. Measurement should be the same distance, if not hopefully you'll have a adjustable track bar and can center it back up.

That might straighten the steering wheel up if it isn't, if it doesn't straighten the wheel the drag link is adjustable.
 
Definitely check too make sure the fans are working ..another quick tip when you see it begin too overheat and your on the road put your heat on full blast had to do this once in the summer time and I was roasting for a 90 mile ride home from wildwood n.j. but I made it without the temperature going into the red..also feel both radiator hoses top and bottom make sure they are both getting hot if not it's an indication the thermostat is stuck closed or like the other guy said an air bubble in the system get a plastic water bottle cut it in half and put it in the hole where the radiator cap was this will allow you to see the bubbles coming up from the radiator and prevent a lose of antifreeze when it starts spewing out also put the heat on high be sure to have the front end higher then the rear wheels so the air bubbles come out ..this may take abot 20 to 30 minutes..I usually put the front wheels on a curb ..good luck brother
 
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