[Scott746]

Hello

I’m pretty boned up on most aspects of my JK. But, I’m no gear head when it comes to engines. My 2015 JK (only 20k miles) sat for about 6 months while waiting on some suspension parts. Started it up, sounded at first like it was missing a cylinder. Ran very rough, stalled when I rev’d it. Started again and ran smoother, but, huge amount of steam (like a steam engine) coming from exhaust. Definitely, positively not oil! Had a sweet terrifyingly familiar antifreeze smell to it.
I’m fearing a cracked block or warped head. But, with these low miles and never overheated it to any concerning degree, that doesn’t seem probable.
Any thoughts are greatly appreciated.
But, the most appreciated reply will be the one that tells me it’s a quick fix!! 😂

 

[Scott746]

Update. No oil in radiator or overflow and oil on dip stick looks fine.
Scratching head.

 

[White Elemant]

I had this exact same thing in my ford during the olden years. Turned out to be a small leak in the head gasket.

 

[White13JKUR]

Most likely a head gasket. The exhaust will have a sweet smell from the burning coolant.

Do a leak down test and a block test.

Get a block tester. Orielly will rent you the tool and you have to buy a bottle of the blue fluid. You get your money backon the tool.

When my head gasket went, iI could also smell exhaust in the radiator overflow tank. Open the overflow tank and take a sniff. If your pentastar has been using the overflow bottle as a bong, then the water wil reek like the exhaust that bubbled up through it.

 

[Scott746]

Most likely a head gasket. The exhaust will have a sweet smell from the burning coolant.

Do a leak down test and a block test.

Get a block tester. Orielly will rent you the tool and you have to buy a bottle of the blue fluid. You get your money backon the tool.

When my head gasket went, iI could also smell exhaust in the radiator overflow tank. Open the overflow tank and take a sniff. If your pentastar has been using the overflow bottle as a bong, then the water wil reek like the exhaust that bubbled up through it.

Great info. Thank you!