Hi guys,
I'm hoping someone can help me out. I have a 2002 Jeep Liberty; 3.7l; 4x4; automatic transmission; 160,00 miles; regularly serviced.
A week ago, the vehicle stalled at a red light. I was able to get it re-started after several cranks and get it back home. It died at nearly every turn when the idle dropped. I also noticed the Check Engine Light came on. Once I got home, I tried to diagnose the problem. The vehicle idled rough while in neutral. When I shifted into gear and the rpm's dropped, it wanted to stall. Once I accelerated, it ran OK but with less power than before.
The next day, I drove it to my local O'Reilly's parts store and had the codes read. It came up with a P0161 code (O2 sensor: Bank 2/Sensor2 heater circuit). I decided that if I was going to replace one, I might as well replace all four.
I replaced all four O2 sensors, fired it up, and head the same problem. I limped the rig into O'reilly's again, checked the code, and got the same thing: P0161. So, I cleared the codes.
Then, I replaced the Throttle Position Sensor. Same problem.
I replaced the Idle Air Control Valve and cleaned the throttle body. Same problem.
With each part replacement, the idle gets a little better.............very little. I've yet to find the root cause though.
Since clearing the coded, the Check Engine Light has not come back on. One thing I've noticed is soot (carbon) on the O2 sensors and coming out of the tail pipe.
The vehicle ran great prior to the initial stall. I've taken immaculate care of it and have had it servided regularly. Spark plugs have less than 10,000 miles on them. Battery is less than two years old.
Now, I'm beginning to think it's a fuel pressure problem but, unfortunately, I have no way of checking the fuel rail pressure. I'm leaning towards a bad fuel pump or check valve/pressure regulator or possibly a leaky fuel injector.......or and bad PCM/ECU? Any input?
Any feedback would be greatly appreciated.
I'm hoping someone can help me out. I have a 2002 Jeep Liberty; 3.7l; 4x4; automatic transmission; 160,00 miles; regularly serviced.
A week ago, the vehicle stalled at a red light. I was able to get it re-started after several cranks and get it back home. It died at nearly every turn when the idle dropped. I also noticed the Check Engine Light came on. Once I got home, I tried to diagnose the problem. The vehicle idled rough while in neutral. When I shifted into gear and the rpm's dropped, it wanted to stall. Once I accelerated, it ran OK but with less power than before.
The next day, I drove it to my local O'Reilly's parts store and had the codes read. It came up with a P0161 code (O2 sensor: Bank 2/Sensor2 heater circuit). I decided that if I was going to replace one, I might as well replace all four.
I replaced all four O2 sensors, fired it up, and head the same problem. I limped the rig into O'reilly's again, checked the code, and got the same thing: P0161. So, I cleared the codes.
Then, I replaced the Throttle Position Sensor. Same problem.
I replaced the Idle Air Control Valve and cleaned the throttle body. Same problem.
With each part replacement, the idle gets a little better.............very little. I've yet to find the root cause though.
Since clearing the coded, the Check Engine Light has not come back on. One thing I've noticed is soot (carbon) on the O2 sensors and coming out of the tail pipe.
The vehicle ran great prior to the initial stall. I've taken immaculate care of it and have had it servided regularly. Spark plugs have less than 10,000 miles on them. Battery is less than two years old.
Now, I'm beginning to think it's a fuel pressure problem but, unfortunately, I have no way of checking the fuel rail pressure. I'm leaning towards a bad fuel pump or check valve/pressure regulator or possibly a leaky fuel injector.......or and bad PCM/ECU? Any input?
Any feedback would be greatly appreciated.
