Lungz

Hey everybody, what’s up? Today I had changed out my O2 sensor because I was getting a trouble code 13, oxygen sensor malfunctioning. I took the car out for a drive and all of a sudden, I developed a miss. I have checked my plugs, only one was a little fouled out, but it does seem like the car is running very rich, I put the old o2 sensor back in, but still is running the same, I bypassed my MSD ignition because I thought it may be malfunctioning, I checked my plug wires. I have yet to check cap/rotor, but I know there is no significant carbon buildup in the cap, and the rotor is new. Does anybody know what could cause a miss suddenly and is there any way to lean the car out a little bit? I will be more than happy to provide more info if it helps get this resolved. One theory I have is that a vacuum leak some place is causing the fuel pressure regulator to malfunction and cause the motor to run rich and foul out the plugs. Another theory is a faulty injector somewhere, anyone's suggestions on what it may be or any suggestions on what to trouble shoot.

TheGreatJ

It's too much of a coincidence that it happened after you changed the O2. Did you reset the computer after installing it? If not you need to....it may be running in "limp home" mode because of the code. Failing that, you could have gotten a faulty O2 (depending largely on what brand you bought....I only run Bosch.)

Lungz

it is a bosch, and Ia ctualy put the old one back in to check that, and I also had the batter disconnected for about 5 minutes, I should actually try that again because I may not have had it off with the old one back in, but it doesn't seem to be that, I agree, too much of a coincidence, but what I was thinking was that because it started running "right", did it cause something to adjust some place else and cause the miss, I will disco the battery and see what that does, thanks for the suggestions, if anyone else has others, jsut in case, that'd be great, thanks. BTW, I have a cap/rotor on the way to try that. On a note, the miss did not occur until I had been on the test drive for about 5 minutes, it was running fine when I left.

Lungz

anybody? I completely reset the computer, no dice, anybody? I have a new theory of moisture in the distributor cap, I know it sounds weird, but when I opened my hood to work on the o2 sensor, some water may have poured off my hood onto the distributor, so I'm replacing the cap to check that, any other suggestions guys?