05 LJ Auto Running Horribly With Several Codes

[ObedaTJ]

I woke up this morning to head to work, and Jeep started horribly. I've never heard it start like this. It's a 05 Unlimited with 76k miles. It's had a check engine on for a while due to a bad O2 sensor. I have been using another vehicle so I was putting it off as it was driving fine. However today, it was not. I believe it's gone in limp mode, it idles very rough, however, the transmission seems to be shifting fine. It almost doesn't wanna start when I turn it on.

Anyways, the check engine light started to flash after driving it to work. Fortunately, I had just gotten to work. I plugged in my scanner to check what codes I was getting, to find that I now have 7 codes.

P0300 (1/7) Pending
Random Misfire Detected
P0157 (2/7) Stored
O2 Circuit Low Voltage
P0161 (3/7) Stored
O2 Heater Circuit
P0057 (4/7) Stored
HO2S Heater Control Circuit Low
P0700 (5/7) Pending
Transmission Control System (MIL Request)
P0157 (6/7) Pending
O2 Circuit Low Voltage
P0161 (7/7) Pending
O2 Heater Circuit

I am assuming the transmission code could be due to the Jeep going into limp mode, however, I am not sure if a bad O2 sensor can cause this, in which case I would be really confused as to where to start. All codes coming on are for the O2 Sensor Bank 2 Sensor 2. I am going to replace that tonight but was hoping any one could give me any insight or tips that may be useful.

Thank you!

 

[JKP]

Being that it's an 05, the PCM is probably on the way out. Talk to Mark @Wranglerfix

 

[ObedaTJ]

Being that it's an 05, the PCM is probably on the way out. Talk to Mark @Wranglerfix

Probably should've mentioned that I already got one of his PCMS in there. Has been for about two years.

 

[JKP]

Well, if the wiring looks OK, I'd check with him to see if it's on the way out.

 

[macleanflood]

How's your crank position sensor?

-Mac

 

[ObedaTJ]

How's your crank position sensor?

-Mac

I believe it’s fine. No codes for it

 

[ObedaTJ]

I just replaced the O2 Sensor 2 Bank 2, which was showing up on most of the codes present. However, now the Jeep will not start.
I did have my old PCM and decided to give it a shot and see if maybe that could be the issue, the old PCM never went bad I just replaced to be safe.
That also did not work. The jeep still won't start, it'll crank and crank but not fire.

 

[JKP]

Does the tach move when cranking?

Do you have fuel pressure? Will it start with starting fluid?

Spark?

 

[ObedaTJ]

Yes I have fuel pressure. The tach does move and I’m not sure about starting fluid

 

[JKP]

Well, the tach working means the crank sensor is working.

For spark you need the crank sensor, PCM, coil to work.

If you have fuel pressure, no need to try the starting fluid. You can use the starting fluid to point to a fuel problem it if runs on the starting fluid then dies out.

I'd check for spark at this point. Maybe a bad coil, or coil wiring.

It should start with a long crank even if the cam sensor were bad.

 

[Wranglerfix]

@ObedaTJ you can send the Pcm to us and we will test it for you and make any necessary repairs.

 

[Magalosh30]

@ObedaTJ you can send the Pcm to us and we will test it for you and make any necessary repairs.

Please wranglerfix I’m in need of replacing or fixing my ecm… car won’t start at this point. Where can I reach you thanks

 

[Bigfoot-NM]

Please wranglerfix I’m in need of replacing or fixing my ecm… car won’t start at this point. Where can I reach you thanks

https://wranglerfix.com/contact/

 

[Dr. Internet]

How old are your plugs? I just changed mine and all my codes went away. '06 LJR, 37k miles.