P0139 code

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

fernandomvy

New Member
Joined
Feb 14, 2018
Messages
8
Reaction score
0
Location
Australia
Whats up jeep lovers!

My engine light lit today. P0139

The car when im stop at trafic lights sometimes go a little rough. But comes back. I knew that could be some sparks or fuel injector issue.

Is there anyway to fix before take to the the mechanic? Injectors cleaners for example? Or this things doesnt work. Change plugs first?

Tks !!
 

ltd02

Comfortably numb
KJ Supporting Member
Joined
Aug 15, 2014
Messages
2,702
Reaction score
241
Location
North Central Maryland
That's a slow bank 1 downstream O2 sensor code. Best to get it someplace where they can watch the voltages as its running. Is this a OE sensor? Sometimes the aftermarket ones like Bosch are a bit slow and don't work well on these 3.7s.
 

benherr

New Member
Joined
Apr 2, 2018
Messages
12
Reaction score
0
Location
CO
I second this advice. I had the same code, replaced the sensor with a Bosch, reset it, and the code came back on in 20 miles. Had another shop check it out and they replaced that sensor with an NTK sensor. Done a couple hundred miles since and the code hasn't returned. Wish I'd know this info prior, would have saved myself some money .
 

fernandomvy

New Member
Joined
Feb 14, 2018
Messages
8
Reaction score
0
Location
Australia
Tks for the replies guys!
But its the sensor itself that is bad or something else could be wrong ? Injectors or sparks for example. Before changing it inwiuld like to know if its sometingh that can be going wrong
 

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
9,098
Reaction score
1,766
Location
B.C. Canada
The set diagnostic code is directly related to the bank 1 downstream O2 sensor, it's probably easier to just replace it, and see how the Jeep runs then.
If you want to pay the extra diagnostics fees, from a snap on ultra scanner, feel free to do that, but I'd do the sensor replacement first, to eliminate the code.
The jeep does like new properly OEM gapped spark plugs every 25-35k miles.
61660[/ATTACH]"]
You must be registered for see images attach

Live data from injectors & coil packs & so much more can be tested/seen on the Snap On Ultra Scanner.
 

Attachments

  • fnAK15T.jpg
    fnAK15T.jpg
    56.7 KB · Views: 0

Members online

No members online now.
Top