Need help diagnosing/fixing our Mojave

[Captain cactus]

We have a 2021 Mojave with just over 80,000 miles. It is on 37s and we have a tazer mini. Until a year ago it had been super reliable with no issues. Then last summer (at about 60,000 miles) after a long drive it began to rumble, lose power and flash warning lights. We pulled off the highway and at first it wouldn’t turn off after repeated attempts. Eventually it did and when restarted it ran like nothing ever happened. I checked for codes and received P0300 P0628 P0171 P0174 P062a. We took it to the dealer and were told it needed an update that would fix the issue. It did not. The same loss of power that seemingly disappeared after a restart continued to occur sporadically. I have since deleted the aux battery and replaced both can bus star connectors behind the glove box with no success. Yesterday my wife drove it a short distance (<30 miles) and it happened repeatedly to the point where it had to be towed back to our house. Any help or advice is greatly appreciated, thank you!

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[ShadowsPapa]

We have a 2021 Mojave with just over 80,000 miles. It is on 37s and we have a tazer mini. Until a year ago it had been super reliable with no issues. Then last summer (at about 60,000 miles) after a long drive it began to rumble, lose power and flash warning lights. We pulled off the highway and at first it wouldn’t turn off after repeated attempts. Eventually it did and when restarted it ran like nothing ever happened. I checked for codes and received P0300 P0628 P0171 P0174 P062a. We took it to the dealer and were told it needed an update that would fix the issue. It did not. The same loss of power that seemingly disappeared after a restart continued to occur sporadically. I have since deleted the aux battery and replaced both can bus star connectors behind the glove box with no success. Yesterday my wife drove it a short distance (<30 miles) and it happened repeatedly to the point where it had to be towed back to our house. Any help or advice is greatly appreciated, thank you!

A Google search shows those are all fuel related - MAF sensors, fuel delivery, etc.
The P0300 is multiple cylinder misfire - meaning you have a fuel system (or sensor) issue causing misfires, that's one of the most common and well-known codes out there.

If I may ask - why did you think the aux battery was involved? Or the CANbus connectors?
Just curious.

Bottom line, you have a fuel system issue. Either you aren't getting enough - fuel delivery or a sensor is malfunctioning/out of range.
--------------------
P0628 - OBD II Trouble Code

RepairPal.com
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Low. The Fuel Pump enables the transfer of fuel from the tank to the ......................
------------------------------

p0171 Code - Fuel Trim System Too Lean (Bank 1)

KBB
https://www.kbb.com › obd-ii › p0171
51
The P0171 code is set when the PCM can no longer compensate for the low fuel condition by adding fuel and will be accompanied by a check engine light. It's ........................
------------------------------------

P062A - OBD II Trouble Code

RepairPal.com
https://repairpal.com › obd-ii-code-p062a-fuel-pump-a-...
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Range/Performance. The Fuel Pump enables the transfer of fuel from .....................
----------------------------

P0174 OBD-II: System Too Lean

RepairPal.com
https://repairpal.com › obd-ii-code-p0174
OBD-II code P0174 indicates the fuel mixture is too lean in Bank 2 of a V engine. Learn what causes a lean condition, such as vacuum leaks or a faulty MAF .................
------------------------------------

 

[Minty JL]

^^^^

Been there already, same codes and drivability issues.

The passenger side valve cover was leaking and flooded the connector for the downstream O2 sensor. I would look there first.

 

[Captain cactus]

A Google search shows those are all fuel related - MAF sensors, fuel delivery, etc.
The P0300 is multiple cylinder misfire - meaning you have a fuel system (or sensor) issue causing misfires, that's one of the most common and well-known codes out there.

If I may ask - why did you think the aux battery was involved? Or the CANbus connectors?
Just curious.

Bottom line, you have a fuel system issue. Either you aren't getting enough - fuel delivery or a sensor is malfunctioning/out of range.
--------------------
P0628 - OBD II Trouble Code

RepairPal.com
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Low. The Fuel Pump enables the transfer of fuel from the tank to the ......................
------------------------------

p0171 Code - Fuel Trim System Too Lean (Bank 1)

KBB
https://www.kbb.com › obd-ii › p0171
51
The P0171 code is set when the PCM can no longer compensate for the low fuel condition by adding fuel and will be accompanied by a check engine light. It's ........................
------------------------------------

P062A - OBD II Trouble Code

RepairPal.com
https://repairpal.com › obd-ii-code-p062a-fuel-pump-a-...
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Range/Performance. The Fuel Pump enables the transfer of fuel from .....................
----------------------------

P0174 OBD-II: System Too Lean

RepairPal.com
https://repairpal.com › obd-ii-code-p0174
OBD-II code P0174 indicates the fuel mixture is too lean in Bank 2 of a V engine. Learn what causes a lean condition, such as vacuum leaks or a faulty MAF .................
------------------------------------

Thanks for your response!
Probably the main reason why I thought it might be the aux battery or the can bus connector is because I talked to several other Mojave owners who had similar issues and was advised that these were the causes, but also that I’m not a very good mechanic

A Google search shows those are all fuel related - MAF sensors, fuel delivery, etc.
The P0300 is multiple cylinder misfire - meaning you have a fuel system (or sensor) issue causing misfires, that's one of the most common and well-known codes out there.

If I may ask - why did you think the aux battery was involved? Or the CANbus connectors?
Just curious.

Bottom line, you have a fuel system issue. Either you aren't getting enough - fuel delivery or a sensor is malfunctioning/out of range.
--------------------
P0628 - OBD II Trouble Code

RepairPal.com
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Low. The Fuel Pump enables the transfer of fuel from the tank to the ......................
------------------------------

p0171 Code - Fuel Trim System Too Lean (Bank 1)

KBB
https://www.kbb.com › obd-ii › p0171
51
The P0171 code is set when the PCM can no longer compensate for the low fuel condition by adding fuel and will be accompanied by a check engine light. It's ........................
------------------------------------

P062A - OBD II Trouble Code

RepairPal.com
https://repairpal.com › obd-ii-code-p062a-fuel-pump-a-...
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Range/Performance. The Fuel Pump enables the transfer of fuel from .....................
----------------------------

P0174 OBD-II: System Too Lean

RepairPal.com
https://repairpal.com › obd-ii-code-p0174
OBD-II code P0174 indicates the fuel mixture is too lean in Bank 2 of a V engine. Learn what causes a lean condition, such as vacuum leaks or a faulty MAF .................
------------------------------------

A Google search shows those are all fuel related - MAF sensors, fuel delivery, etc.
The P0300 is multiple cylinder misfire - meaning you have a fuel system (or sensor) issue causing misfires, that's one of the most common and well-known codes out there.

If I may ask - why did you think the aux battery was involved? Or the CANbus connectors?
Just curious.

Bottom line, you have a fuel system issue. Either you aren't getting enough - fuel delivery or a sensor is malfunctioning/out of range.
--------------------
P0628 - OBD II Trouble Code

RepairPal.com
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Low. The Fuel Pump enables the transfer of fuel from the tank to the ......................
------------------------------

p0171 Code - Fuel Trim System Too Lean (Bank 1)

KBB
https://www.kbb.com › obd-ii › p0171
51
The P0171 code is set when the PCM can no longer compensate for the low fuel condition by adding fuel and will be accompanied by a check engine light. It's ........................
------------------------------------

P062A - OBD II Trouble Code

RepairPal.com
https://repairpal.com › obd-ii-code-p062a-fuel-pump-a-...
OBD-II Code Decreased engine performance is defined as a Fuel Pump "A" Control Circuit Range/Performance. The Fuel Pump enables the transfer of fuel from .....................
----------------------------

P0174 OBD-II: System Too Lean

RepairPal.com
https://repairpal.com › obd-ii-code-p0174
OBD-II code P0174 indicates the fuel mixture is too lean in Bank 2 of a V engine. Learn what causes a lean condition, such as vacuum leaks or a faulty MAF .................
------------------------------------

thanks for your reply, I really appreciate it!
Probably the main reason I thought it might be the aux battery or the can bus connector is because I’m very new to working on my own jeep and not a very good mechanic my wife posted about the issues in a facebook gladiator group and many people who had similar problems suggested deleting the aux battery and replacing the can bus connector, which did not work. Also, the fuel related codes never came back after the first incident, and still there are no codes, except for a strange one saved by the tazer, something about a secret code

 

[Captain cactus]

^^^^

Been there already, same codes and drivability issues.

The passenger side valve cover was leaking and flooded the connector for the downstream O2 sensor. I would look there first.

That’s great, I’ll definitely look into it, thanks for your response, I appreciate it!

 

[Minty JL]

That’s great, I’ll definitely look into it, thanks for your response, I appreciate it!

Hopefully it will save you time and headaches

 

[calminiboxer]

I have had all the same issues and it has been the tazer every time, I don't leave it in anymore and have not had any of the issues since. The worst part is I have to press the start/stop button every time. Small inconvenience compared to the issues from the tazer.

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