Major run problems 2002 3.7, Any help will help

[jhc7399]

First off, hello everyone. I have been browsing the forums for a few days looking for answers and the closest post with my issues never responded how they fixed the issue.

I have a 2002 Jeep Liberty Sport, 3.7, 2 wd.

Wednesday night I was driving home from work, about 7 miles total. Stopped by the store and noticed the engine sounded a little different? Well I got to about 2 miles from the house and she started trying to stall, so I pulled over and things just got worse from there. I had to use Nuetral and the brake pedal like a clutch to make it home. By the time I got there I was lucky to be able to go 10 miles an hour. Severe missing, engine races from 2000 rpm down to 200 rpm, tries to stall then races back up again, repeat? Gets alot worse as it warms up. Also a pretty bad smell while it is trying to run.

Friday night I replaced the MAP sensor and the PCV valve, no change. After I replaced those I made it up to Autozone about a mile away and they ran a diagnostic, brought back 10 codes. By the time I made it back to my house same thing, no power, engine racing, trying to stall. Sunday I replaced the Throttle Position Sensor and the plugs, still the same. I tried to do both of the O2 sensors on bank 1 but neither will budge. I am seriously thinking about going to the dealer and letting them diagnose it instead of the witch hunt and burning up my money.

These are the codes:
....................................
P0108: MAP SENSOR VOLTAGE TOO HIGH
P0118: ENGINE COOLANT TEMPERATURE SENSOR VOLTAGE TOO LOW
P0132: O2 SENSOR 1\1 CIRCUIT VOLTAGE LOW
90138: O2 SENSOR 1\2 CIRCUIT VOLTAGE HIGH
P0171: 1\1 FUEL SYSTEM LEAN
P0300: MULTIPLE CYLINDER MISFIRE
P0303: CYLINDER #3 MISFIRE
P0305: CYLINDER #5 MISFIRE
P0442: EVAP LEAK MONITOR MEDIUM (0.040) LEAK DETECTED
P0455: EVAP LEAK MONITOR LARGE LEAK DETECTED
.................................................. ...

My boss at work is an ASE Master Mech and is telling me clogged Catalyic converter(s). I am on my way to see if there is anything rattling around when I tap them with a hammer. Don't really know what else to do after that besides start replacing sensor one at a time?

Any ideas would be very much appriciated and I promise I will post the solution when one is found...

Thanks Jeff

 

[1BADKJ]

Bad smell, o2 codes, misfires; sounds like possible cat problem.

 

[Leeann]

^ yup, that's what it sounds like to me.

Spray PB Blaster around the threads of the O2 sensor. Heat up the bung the O2 sensor screws into with a propane or MAPP gas torch (just the bung, not the sensor). Get it hot (but be careful). Then unscrew the O2 sensor with an O2 sensor socket and breaker bar.

Once you get both out, see if the truck will run better. If it does, your cats are plugged. Don't run it too long that way, all you're doing is relieving some of the exhaust backpressure and it will be loud.

 

[sparker]

Hi All,

This is the closest thread I have found to the problem that I am having. I have a 2005 Jeep liberty 3.7. I started with 10-12 codes like posted above and worked it down to codes 300 and 306, now I am stumped. We have replaced:tps, cps, ckps, o2 sensors, plugs, coils and injectors all around. Compression testing is perfect in all cylinders, I did take it in for a valve head cleaning and CAT cleaning. I do not have any stalling or surging anymore but the miss is still ever present. Any ideas of where to go next?