wallisek
NAXJA Forum User
- Location
- Newberg, Oregon
At wits end, tired and all greasy dirty. Need some ideas from clear heads. I was driving home yesterday from work and the Jeep started to give me fits. It was almost 100 F and I have a 40 mile one way commute home, mostly freeway. Engine stayed at a solid 210 the whole trip. Anyways, I got off the freeway and noticed the idle seemed a bit off / rough. A few miles through stop and go traffic, it got progressively worse. By the time I made it into town, I was having to give it light throttle to keep from dying at stops Accelerated fine and seemed like it had plenty of power.
I literally pull into the drive way and the engine is shaking / stumbling so bad the shifter is bouncing around. CEL comes on and throws a P0306 (Misfire # 6), I shut it off. I thought maybe this was the typical heat soak issue so I let it cool off and tried again cold. Same terrible stumble, barely idled.
CPS test failed so I replaced it with a new one. Started right up and idles a lot better, but now sounds like a carb'd v8 with. A bit of rough idle which is completely random. If I give it throttle, it will run fine for a few seconds and then drop 100-200 rpms and then I hear a pop from the engine bay.
I swapped over the coil pack and IAC from my wife's Jeep, no change. Fuel pressure is good, 50psi, 40psi after shutoff / 5 mins. Injectors tested with my multimeter, they all were within spec. Pulled plugs which aren't that old, look perfectly clean. Compression test was good, all cylinder were 5-10 psi of 150. 170-180 if I cranked it for a bit.
No signs of oil/water mix. I've taken very good care of my Jeep, I'm OCD when it comes to maintenance. 10w30 full synthetic every 6-7k. At this point, I'm at a loss. The only things I weren't able to replace or test is the TPS, cam sensor and MAP sensor. Another thing comes to mind is maybe the timing chain jumped a tooth? O2 sensors were replaced last year and I no longer have a cat.
2001 XJ 5spd 4.0 w/ 215k.
Any ideas? This is my only vehicle besides my wife's, and we both work. (two projects in the garage but they aren't road worthy yet lol ) I'm getting tired of maintaining a fleet of vehicles, I'm about ready to treat myself to a new commuter car, I've never actually owned a new car before.
I literally pull into the drive way and the engine is shaking / stumbling so bad the shifter is bouncing around. CEL comes on and throws a P0306 (Misfire # 6), I shut it off. I thought maybe this was the typical heat soak issue so I let it cool off and tried again cold. Same terrible stumble, barely idled.
CPS test failed so I replaced it with a new one. Started right up and idles a lot better, but now sounds like a carb'd v8 with. A bit of rough idle which is completely random. If I give it throttle, it will run fine for a few seconds and then drop 100-200 rpms and then I hear a pop from the engine bay.
I swapped over the coil pack and IAC from my wife's Jeep, no change. Fuel pressure is good, 50psi, 40psi after shutoff / 5 mins. Injectors tested with my multimeter, they all were within spec. Pulled plugs which aren't that old, look perfectly clean. Compression test was good, all cylinder were 5-10 psi of 150. 170-180 if I cranked it for a bit.
No signs of oil/water mix. I've taken very good care of my Jeep, I'm OCD when it comes to maintenance. 10w30 full synthetic every 6-7k. At this point, I'm at a loss. The only things I weren't able to replace or test is the TPS, cam sensor and MAP sensor. Another thing comes to mind is maybe the timing chain jumped a tooth? O2 sensors were replaced last year and I no longer have a cat.
2001 XJ 5spd 4.0 w/ 215k.
Any ideas? This is my only vehicle besides my wife's, and we both work. (two projects in the garage but they aren't road worthy yet lol ) I'm getting tired of maintaining a fleet of vehicles, I'm about ready to treat myself to a new commuter car, I've never actually owned a new car before.
Computer finally threw another code, P0123. TPS voltage too high. 5v on one wire and the middle wire shows .76v fully closed, 4.46v fully opened. The IAC was replaced a while back with a knockoff, MAP sensor was replaced as well with a junkyard pull. The TPS is the only factory part left still connected, maybe it is time to ditch it.
