Notes: Poor side crash test ratings from the IIHS are really no surprise.


really awful
Crashes / Fires:
1 / 6
Injuries / Deaths:
1 / 0
Average Mileage:
23,268 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2012 Jeep Wrangler engine problems

engine problem

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2012 Jeep Wrangler Owner Comments (Page 4 of 5)

« Read the previous 20 complaints

problem #34

Feb 272013

Wrangler 6-cyl

  • 4,000 miles


While driving to work after clearing snow from my vehicle...there remained a large piece of ice that would not readily disengage from Jeep while trying to clear snow and ice. The hood has a deep well in the shape of a horse shoe...the design is a flaw (replicated from another design from aev but when put into production they left out drainage design) because water accumulates on the hood while warm and driving in snow etc...when shut down the water that remains on the hood refreezes and can not be removed unless you care about damaging the paint by forcefully chiseling it away. Long story short I was on the highway and could see that the engine heat was melting the ice panel and sure enough it flew up and over my windshield not without smashing the header of my windshield and then near missing the vehicle that was in back of me. The design will definitely cause damage in the future this I can say without hesitation. If Chrysler had chose the option to vent the water out of the hood there would be no problem. Unfortunately they did not. Now every winter I pray that I am not traveling during heavy new england weather because this issue will repeat itself as many times as we get snow.

- Providence, RI, USA

problem #33

Jan 022013


  • 26,618 miles
The contact owns a 2012 Jeep Wrangler. The contact stated that the check engine warning light remained illuminated. The vehicle was taken to the dealer where a diagnostic was performed, which located a failure at the exhaust gas recirculation valve. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was 26,618 and the current mileage was 50,100.

- Clifton , VA, USA

problem #32

Aug 032013

Wrangler 6-cyl

  • 18,500 miles
Cylinder 6 misfire - requires new engine head. Manufacturer has had parts backordered, and service centers are instructing customers to continue driving vehicle until part can be replaced. Judging by internet posts this seems to be a common defect that could potentially strand drivers or cause engine failure while in motion. Manufacturer is on 3rd version of part and has not alerted customers to the issue or provided resolution to the continued issue.

- East Longmeadow, MA, USA

problem #31

Jun 272013

Wrangler 6-cyl

  • 24,514 miles


I have a 2012 Wrangler sahara 4dr and this past week I had to tow my Jeep into a dealership in texarkana. I was driving 45 mph and not trying to gun the rpms. I had total shutdown but was able to get off the road. The dealership hooked it up and told me that my asd 25 amp fuse had blown but couldn't figure out why. My Jeep ran okay for much of the day but by night it blew another fuse as I accelerated from a green light and into the intersection. I replaced it with another 25 amp fuse but fear that if I put a 30 amp in that it would be too much for a burn out but I wanted to make sure I got home. I drove back home (an hour drive up and down hills) and it seemed to always want to ramp up the rpms suddenly. I would love to know if anyone else has had this kinda issue? I have less than 25,000 miles on my Jeep. Update... I have now had three fuses blow and two tows to dealerships because I couldn't keep a good fuse. I hope someone can please help me point out the direction the dealership needs to be looking for. This is getting frustrating. It seems to blow a fuse when I hit any type of bump in the road. No electrical mods were made except my warn winch, which was installed at the dealership for warranty reasons. Currently my Jeep remain in a tow yard until tomorrow where they tow it back to the dealership * no warning lights are indicated * new air filters * no electrical mods * factory sound system * rides rough * when fuse blows, total vehicle shutdown occurs including power steering and brakes.

- Shreveport , LA, USA

problem #30

Mar 142013

Wrangler 6-cyl

  • 13,000 miles
Windshield wipers come on randomly while driving. Service states there is nothing they can do. Check engine light also on. Service repaired cracked cylinder head. 5 days later check engine light is back on.

- Monmouth Junction, NJ, USA

problem #29

Mar 222013


  • 21,314 miles
The contact owns a 2012 Jeep Wrangler. The contact stated that while driving 35 mph, the malfunction indicator light illuminated as the vehicle began to loose power. The vehicle was taken to the dealer for inspection and they stated that cylinder two had misfired and the cylinder head needed to be replaced. The vehicle was not repaired. The manufacturer was notified but provided no assistance. The failure mileage was 21,314.

- Wellington, FL, USA

problem #28

Mar 132013


  • 17,300 miles


The contact owns a 2012 Jeep Wrangler. The contact stated that while driving approximately 35 mph, an unusual ticking noise emitted from the engine with the illumination of the check engine warning indicator. The failure occurred until the engine was turned off. The vehicle was taken to an authorized dealer for diagnosis. The technician stated that the failure was contributed to a faulty engine head and valve. The vehicle was not repaired. The manufacturer was not notified of the problem. The approximate failure mileage was 17,300.

- El Paso, TX, USA

problem #27

Feb 192013


  • 3,500 miles
The contact owns a 2012 Jeep Wrangler. The contact stated that the engine made a loud ticking noise on the driver's side. The vehicle was taken to the dealer who was able to duplicate the failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 3,500 and the current mileage was 4,500.

- Cape Coral , FL, USA

problem #26

Feb 202013

Wrangler 6-cyl

  • 16,552 miles
2012 Jeep Wrangler: Sudden unintended acceleration while driving at 50mph. Rpms suddenly and unexpectedly exceeded 4K while brake pedal was applied in an attempt to slow the vehicle down. Electronic throttle control ("etc") warning light activated. Engine rpms eventually slowed and I was able to get the Jeep off the road, park, and shut off the engine. Upon restart, the engine rpms were above 4K without any accelerator pedal input, the gas pedal was "floored" on its own, and the etc warning light was activated. I recorded the dash board with my iphone because what was happening was beyond belief.

- Gainesville, VA, USA

problem #25

Aug 012012

Wrangler 6-cyl

  • 4,000 miles
2012 Jeep Wrangler started to have engine tick. Took to 2 local garages, and they would not work on it. One said it was a Chrysler restricted warranty work the other it was within the normal sound of the engine. It did not make ticking sound when purchased. I contacted Chrysler to register a complaint and they said they had no idea that there was anything wrong. I had to take back to purchase garage where I had to push for it to get fixed. That was November. Engines in some of the 2012 Jeep had a valve cut wrong and Chrysler will only send out 1 valve per engine per week. My mileage has dropped and the ticking is worse. I have also noticed a bad "miss" when at idle. I was told it was ok to drive. It is getting worse. It is scheduled to go in the second week of January to get fixed. I have yet to hear anything from garage to let me know the part is in. I had 4 other Jeep Wrangler before me getting the part in to be fixed, and was told it was going to take a week or two at the garage. I only have 9200 miles on the Jeep.

- Cadiz, OH, USA

problem #24

Nov 022012

Wrangler 6-cyl

  • 15,400 miles


Vehicle is currently (Dec 2012) at dealer having heads/valves replaced (10th day after waiting 10 days for parts), original report 9 Nov: Idling engine continues to be very rough, much rougher than when reported to dealer on November 9 2012, dealer did PCM reflash/update as stalling maneuver, after which problem worsened and mil came on vehicle is vibrating abnormally when stopped and idling, all passengers feel the car shaking, almost stalls at times idling engine changes speeds and sound intermittently and is running very loud engine always had slight ticking on left side since new but was never loud or rough loss of power felt at acceleration at top of gears (manual) white exhaust emissions after cold start, this never happened before engine light mil is on and off repeatedly - reads P0306 cylinder 6 misfire gas mileage severely affected (approx 25% worse), car now has 18K miles; dealer said it was ok to drive it - however driving it may cause other damage this is 3rd visit to dealer - when problem first reported dealer service dept said I might have put water in the gas. I have had to push the dealer to fix this and the general attitude has been adversarial and not helpful.

- Mamaroneck, NY, USA

problem #23

Aug 252012

Wrangler 6-cyl

  • 16,217 miles
Many major mechanical issues for this vehicle 1) 6th cylinder head on the new penstar engine needed to be replaced 2) wind air leak causing whistling in the cabin 3) serpentine belt shredded and cracked 4) belt tensioner was binding and needed to be replaced 5) major vibrations- intake and exhaust phasers shorted 6) motor mounts worn 7) vibration got worse motor mounts trans and exhaust had to be remounted.

- Alexandria, VA, USA

problem #22

Nov 202012

Wrangler 6-cyl

  • 23,000 miles
Check engine light came on. Initial trip to dealer and they decided to just reset the codes. Light came back on the next day. Return to dealer and they reported a bad cylinder head. Told me to keep driving, car now has more engine noise and power lose. (as a side note the dealership has also replaced, about 3 weeks ago, a"bad"pvc valve which resulted in the air filter and housing coated with about a 1/2 inch of engine oil.). have been waiting on parts going on 10 days. Not stupid enough to keep driving the vehicle as the dealer suggested. It is irresponsible for dealers to tell clients to keep driving when this vehicle has power issues and appears at risk for stalling. This is an accident waiting to happen.

- Lexington, SC, USA

problem #21

Nov 282012


  • 805 miles
I experienced a serious problem with my 2012 Jeep sahara. After accelerating and passing another car while driving, I lifted off the accelerator, but my Jeep continued to accelerate. I tapped several times on the accelerator, then tapped the brake a couple of times in case the speed control somehow engaged. I then tried to see if I could lift the accelerator from below with my foot, but it wasn't depressed. The Jeep was continuing to accelerate and at this point I was going well over 80 mph. Finally I was left with no choice but to depress the clutch and take the vehicle out of gear. I quickly shut down the engine as the revs went through the roof. I coasted onto a side road and attempted to restart my Jeep, but it wouldn't turn over. I turned the ignition to the off position and removed the key, put the key back in and turned the ignition at which point it turned over and after about 5 or 6 secs it finally restarted and everything seemed normal. I checked around the accelerator and the floor mat was securely in place and there was nothing around the accelerator to cause it to stick. I have never experienced anything like this before in my life and am 110% sure that the problem was not driver error. My feet were completely off any of the peddles while the Jeep continued to accelerate and as I had a clear road ahead of me, I very methodically and calmly took the actions I outlined above in the attempt to reduce the engine speed with no affect until I finally had to shut it down.

- Peoria, IL, USA

problem #20

Nov 212012

Wrangler 6-cyl

  • 12,000 miles
Chrysler pentastar 3.6L recall needed for major defect that is requiring major engine rework and complete cylinder head replacement around 12K miles. This is going on now and needs public announcement/recall. Please google "cylinder 2 misfire pentastar" this is already reported by ~25% of 2012 owners.

- Mission Viejo, CA, USA

problem #19

Aug 062012


  • 14,000 miles
Really have 3 issues with this vehicle. The first is that the engine began to tick noticeably at around 5000 miles, sound definitely coming from #2 cylinder. Was initially told not to worry, noise was normal, oddly it did not tick previously. The short story is that it set a P0302 code at around 12,000 miles. Chrysler did not authorize a rental and the dealer was less than cordial. They put the thing back together and damaged an emissions valve, so more delay. Get the vehicle back, ran silent for 2,000 miles, the tick is back. Now at 19,000, no code yet, but I fear its coming. Problem #2, exhaust smell, get it nearly all the time, especially under load, no resolution yet. Problem #3, wet carpet on drivers side, no resolution yet. Oh, I forgot to mention, there is a fourth, I have just installed the third windshield in less than 6 months. Its not the quality of the glass, its the steep angle of the windshield, but that's what you get when you buy a Wrangler. I have been loyal to us brands, this is our 32nd new vehicle, won't by a Wrangler again.

- Waterbury, CT, USA

problem #18

Sep 042011

Wrangler 6-cyl

  • 18,000 miles
3.6 liter V6 pentastar driver's side cylinder head began ticking and failed while returning home from a trip. Cylinder head failed after less than 10 month of service. Repair time was over two weeks due to parts availability. Chrysler gave no explanation for failure.

- Manvel, TX, USA

problem #17

Sep 112012

Wrangler 6-cyl

  • 2,500 miles
Loud ticking noise coming from left side of the engine. The engine was quiet previously, there was no ticking noise.

- New Phila, PA, USA

problem #16

Jul 102012

Wrangler 6-cyl

  • 11,800 miles
I bought my 2012 Jeep Wrangler unlimited sport in November 2011. It was working just fine until the summer of 2012 when my wipers would turn on all by themselves for a few seconds, and then off again. This happened several more times during the summer. In addition, the radio would just power off. The only way it would come back on was to hit the top of the dash and it powered back on. Took it in and they flashed a module which stopped the wiper issue but not the radio problem. This was July 2012. After that in same month, I noticed an engine light came on solid. Took it in, they reset it saying it was a cylinder #2 misfire. People on were talking about it too (see jk section and look for "ticking pentastar" thread). It was the biggest thread actually. Apparently, over a hundred owners on just this site alone had to have their head replaced. Wtf? the light came back on a couple days later so I took it back in. They confirmed the same result and told me they would order a new head. The local dealer here in savannah (hoover) told me it was in. Took in the Jeep and they said it would take 2-3 days. Big lie. After 3 days, I called to get status and they told me it would be 2-3 weeks!!! there were several people in front of me with same issue and only one guy fixing them. With a major issue like this on a brand new vehicle, this calls for a class-action lawsuit. I get small glitches happening but a new head"?" they did not change anything on the 2013's so this will likely be a huge headache for Jeep. Be warned!!!!

- Richmond Hill, GA, USA

problem #15

Sep 132012

Wrangler 6-cyl

  • 2,463 miles
Loud ticking noise coming from the engine. The engine was quiet previously, there was no ticking noise.

- Hilmar, CA, USA

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