Hey everyone, running into some fresh error codes and hard idling after having a shop do some exhaust work. I have a 2001 TJ Sport.
Long story short, I had 4 new o2 sensors(NTK), flowmaster direct fit cats, and a banks exhaust bolted on this week by a shop. When I picked it up the guy had told me he reset the computer and only code remaining was a small evap leak, but the Jeep sounded good and I drove it home which was only a mile away. A few days later after driving around town I started noticing significant idle issues and the codes were showing as misfire(203/303) and a blinking CEL(bad news). Google tells me the blinking light usually indicates a severe engine misfire allowing unburned fuel to be dumped into the exhaust system, which is indeed how it smelled and acted. I figured I would change the spark plugs(champ 7034) and clean the throttle body. I pulled the throttle body off to clean it along with the IAC, and it was pretty filthy. It improved some of the idle issue and the blinking CEL, however still wasn’t quite right. For example, there would be some surging in the rpms, especially throttling down. Now the codes showing are 203,300,302,303,456. Whenever I break too aggressively when coming to a stop or even turn, the rpms crash and the Jeep almost stalls out.
After all that, could a dud o2 sensor be showing as a misfire and not a direct o2 sensor error code? Or are we looking at something else faulting out at the same time? Thanks in advance and let me know if anyone needs more info.
Long story short, I had 4 new o2 sensors(NTK), flowmaster direct fit cats, and a banks exhaust bolted on this week by a shop. When I picked it up the guy had told me he reset the computer and only code remaining was a small evap leak, but the Jeep sounded good and I drove it home which was only a mile away. A few days later after driving around town I started noticing significant idle issues and the codes were showing as misfire(203/303) and a blinking CEL(bad news). Google tells me the blinking light usually indicates a severe engine misfire allowing unburned fuel to be dumped into the exhaust system, which is indeed how it smelled and acted. I figured I would change the spark plugs(champ 7034) and clean the throttle body. I pulled the throttle body off to clean it along with the IAC, and it was pretty filthy. It improved some of the idle issue and the blinking CEL, however still wasn’t quite right. For example, there would be some surging in the rpms, especially throttling down. Now the codes showing are 203,300,302,303,456. Whenever I break too aggressively when coming to a stop or even turn, the rpms crash and the Jeep almost stalls out.
After all that, could a dud o2 sensor be showing as a misfire and not a direct o2 sensor error code? Or are we looking at something else faulting out at the same time? Thanks in advance and let me know if anyone needs more info.