JK 2012 Engine Tick and Fuel Economy Issue?
 

First just wanted to shout out to the community and say thanks for all the valuable information I've found on this forum.

Second, I am curious if anybody has seen an issue with a 2012 JK engine tick on the driver side that would cause a MPG issue. I'm currently seeing a similar tick to what others have reported but at the same time my fuel economy is hovering at about 12 mpg street and 14-15 freeway. I've already taken my car into a dealer and they said that they couldn't find anything wrong since the check engine light wasn't lit. I only have 13000 miles on the vehicle currently and the only mods are a new front bumper and a MyGIG Lockpick which I don't think could cause the issues.

Does anybody have any suggestions or seen this issue previously, I haven't been able to locate any threads with similar problems for the 3.6 Pentastar JK yet?

Here's a couple of threads to get you started. It seems Chyrsler knows there is a problem, but are just buying some time. Basically they won't due anything until that check engine light comes on and throws a code. They may reflash your computer and send you off your way. Like others, you just have to continue to drive it until you get that engine light to turn on..

https://www.jk-forum.com/forums/stoc...er-6-a-220681/

https://www.jk-forum.com/forums/stoc...ngines-227770/

https://www.jk-forum.com/forums/jk-t...-fixed-225376/

:beer:

This is a common issue with the 2012. I had the same thing. The heads were milled wrong. Its covered under warranty. Take it to your dealership. They will fix it. Mine was done and it runs great now. Don't wait to long it will start throwing codes and it take upto a couple of months to get the head in. Your dealership is playing dumb. This is a common problem with the 3.6 not just in the jeep. The Caravan's have the same issue.

I would go right back to the dealership and insist they contact Chrysler regarding it. Chrysler has to replace the head, as its under warranty.

Ok, I took my car to a different dealer and they too said that it was a normal noise for the Pentastar engine to make. I took a video this evening to illustrate the noise if any of you mind taking a listen to see if you think that there is indeed something wrong as I suspect.

http://youtu.be/7YaoQn8XlWI I am unsure how to get the dealer to acknowledge the issue if there is a problem since now two of them have told me that they cant do anything.

Do an Internet search, there is a lot of info about the "Pentastar tick" that not only affects the Wranglers but also other Chrysler vehicles. Below is what I found thru Motortrend. There are also numerous youtube videos about the issue. Print some materials out and show the dealership or you can escalate your case directly thru Chrysler. But as previously mentioned, in most cases nothing is done until a check engine light comes on and a code is thrown. Best of luck :beer:

http:// wot.motortrend.com/we-hear-chrysler-pentastar-v-6-could-experience-warped-cylinder-heads-245941.html#axzz2Qsw2DcJ9

http://i215.photobucket.com/albums/c...ps2c0c52ba.jpg
http://i215.photobucket.com/albums/c...pse283b095.jpg

Thats certainly not a normal engine noise no matter what they say, id show that video to the dealer Manager, if that does not assist, i would Email Chrysler with the video and see what they say.

I have 9000 miles on mine, and it guess it ticks. I figure if it starts to throw codes. I'll just clear them for awhile. That way I am thinking a reflash won't work. From what I hear the reflash just changes the number of misfires before it throws s code. The gas mileage does suck on these new motors if you have any kind of right leg muscle. My '98 Cherokee get way better gas mileage.

I bought my JKU 12 in August and is my first jeep so I'm trying to be forgiving when I hear ticks thinking it might be normal for a jeep. However I def here something on mine at times. Plus I did sooo much research on MPG and decided on my jeep based on the advertised MPG. I'm averaging about 16.5mpg. I love my jeep and summertime makes owning a jeep better but damn I feel like jeep could have done something to get this efficiency better and not inflate the numbers for new buyers.

Whats weird is that at first (Before September 2012) I had just about the advertised mileage for my Jeep. I really don't know what caused it to suddenly drop and I had assumed at least before I really paid attention to the ticking noise that it was because of winter mixture gas.

If this helps, here is what my mileage looks like in the first 20,000 miles on my 2012 JKU with manual trans and 3.73 rear. I did see about 0.5mpg drop with cold temperatures and winter gas. I now have 26,000 miles and will be updating the chart soon. Below 15.5 is towing. Above 19.5 is 100% highway.

Mine runs great , I had an awesome dealer do my head swap here near Houston where I.live....I.had no tick, no cel , nothing . They just agreed to fix it . I get 22 on the highway and 18 in town ....I love my powerhouse pentastar! ...:beer:

In the absence of throwing a code, I doubt that you'll get any action from the dealer.
I have a '12 JKUR manufactured in Aug. '11, and in July of 2012 it threw a code. Dealer flashed it, and it was only about 30 min. later that it threw the code again.
I went to a second dealer, and they didn't mess around; they did a "leak down" test and that confirmed the head/valve problem; that's the test that has to be performed.

But to answer your question about mileage, I got the results of the leak down test a couple of days before I was scheduled to take a road trip to Montana. The dealer said "no problem; drive the Jeep." I did, and I don't think that my mileage was any different compared to the months prior (and I put 3300 miles on during that trip).
I'm not saying that the head problem can't affect mileage, but I don't think you should try to equate your mileage to a mechanical defect.

Again, I believe that there is only one way to absolutely diagnose the problem. If you wanted to take the chance and pay for the leak down test and it was positive, perhaps you'd have some recourse. Otherwise, wait for the code to throw.