PO175 and PO300 codes

DBats

DBats

New member
Hey all, hope everyone had a great holiday!

I seem to have run into my first issue with my Jeep and I was wondering if anyone had some advice on where I should start to get this taken care of.

I was pulling up to an intersection and stopping at the light, at full stop the jeep suddenly began to idle very rough typical of a misfire, the jeep warning chime also began to sound and the CEL began to flash on the dashboard but it didn't stay on. I then kept driving and the jeep was very sluggish and unresponsive and after a few hundred feet down the road the chime sounded again and the CEL flashed again. However, after one more stop before getting to my house the jeep evened out just as quickly as it started to run like trash, the CEL didn't return and the jeep ran normal the rest of the ride home despite my attempts to replicate the issue where I would stomp on the pedal, stop for a bit, let it idle, but nothing would make it run shitty again.

When I got home I pulled out my flashpaq and ran the diagnostic which came up with two codes (PO175 fuel too rich 2/1) and (PO300 multiple cylinder misfire).

I have no aftermarket mods done to the engine, i.e CAI or TB spacer or anything of that nature. Jeep is a 2012 with 52k

Anyone else dealt with this these problems before? Where should I start looking?

Thanks in advance!
 
aldaman

aldaman

Member
The 2nd code could be that infamous cylinder head issues that some '12s & '13s have had. The dealerships replaced the heads under warranty....
 
WJCO

WJCO

Meme King
DBats said:
Hey all, hope everyone had a great holiday!

I seem to have run into my first issue with my Jeep and I was wondering if anyone had some advice on where I should start to get this taken care of.

I was pulling up to an intersection and stopping at the light, at full stop the jeep suddenly began to idle very rough typical of a misfire, the jeep warning chime also began to sound and the CEL began to flash on the dashboard but it didn't stay on. I then kept driving and the jeep was very sluggish and unresponsive and after a few hundred feet down the road the chime sounded again and the CEL flashed again. However, after one more stop before getting to my house the jeep evened out just as quickly as it started to run like trash, the CEL didn't return and the jeep ran normal the rest of the ride home despite my attempts to replicate the issue where I would stomp on the pedal, stop for a bit, let it idle, but nothing would make it run shitty again.

When I got home I pulled out my flashpaq and ran the diagnostic which came up with two codes (PO175 fuel too rich 2/1) and (PO300 multiple cylinder misfire).

I have no aftermarket mods done to the engine, i.e CAI or TB spacer or anything of that nature. Jeep is a 2012 with 52k

Anyone else dealt with this these problems before? Where should I start looking?

Thanks in advance!
Click to expand...

If this occurred shortly after a fill-up, it COULD be related to poor fuel. I also would check all the wiring around that o2 sensor to make sure it isn't broken or rubbed on something. Chances are that the P0300 code (misfire) is causing your o2 sensor to read rich and setting the other code. If you don't have any isolated cylinder misfire codes in the future soon, I would recommend a good fuel injection service and intake decarb just to see if there is any varnish or carbon that could be causing it.
 
DBats

DBats

New member
Could is also be the other way around? Could the o2 sensor be messing up giving the rich reading and causing the misfire that way?

I don't know how the flashpaq inventories the codes but the PO175 came up first followed by the PO300
 
WJCO

WJCO

Meme King
DBats said:
Could is also be the other way around? Could the o2 sensor be messing up giving the rich reading and causing the misfire that way?

I don't know how the flashpaq inventories the codes but the PO175 came up first followed by the PO300
Click to expand...

That is possible. Can your Flaspaq read fuel trims or 02 readings? If so, you may be able to tell if the sensor is sticking.
 
DBats

DBats

New member
Well I thought the issue had resolved itself as I could not replicate the issue all last night or this morning when I drove around. However, sure enough after stopping at the gym for a few hours I came back out to head home and the issue came back, same deal flashing CEL and super choppy idle. But then like magic it's gone and now I can't get it to come back again....

I'm running a can of seafoam through it now to see if its maybe a stuck injector, my next step would be to pull out the MAP sensor and throttle body and see if they need cleaning.

Does anyone have a rough idea of where all the vacuum hoses on this thing are? I might check there too.
 
You must log in or register to reply here.
Top Bottom