Random Misfire P0300 Help Needed

[fred007]

I have an LS1 from a 2000 vette in my Jeep. While out wheeling the other day, it started running really rough and the MIL was blinking. Got it back
to the lodge and wished i had my scanner. Waited a bit, and it started right up and everything worked fine. Went wheeling the next day without any issues.
Had it happen once more on that trip and when we got back ordered and installed a new set of stark plug wires. Just had the same issue tonight. Got it
home, left it running bad and ran for the scanner. Just got the scanner running and it started running just fine. Read a bit on this error code and think it
might be the O2 sensors. I don't have cats, so only the front sensors just below the headers. At this point was thinking I would replace the O2 sensors based
on what I was reading about the random P0300 codes here. I can also do the plugs as that is fairly straight forward. Thinking sensor or electric because it
"comes and go's" so is very inconsistent.

Any thoughts/ideas would be appreciated.

[FinZ28]

How many miles on the O2 sensors? Check your plugs and wires and make sure they are all in good shape and properly connected, then go from there.

[fred007]

I really don't know how many miles, I picked up the engine from another guy that had it in his Jeep and wrecked it. Since doing the conversion, I have put about 12k on it, and was told it had about 35k when I got it. I did just replaced the plug wires, think I will do the plugs and O2 sensors just in case. Where we go with the Jeep, I really need it to be dependable as it can be a very long walk back if something goes wrong. Thanks.

[cammed goat]

Has the engine been tuned to have the second O2s, or lack thereof, deactivated?

[fred007]

Yes, i purchased the engine with the computer, harness and program already running. But also had a local tuner help me out here. Also, this problem has just recently started, I have about 12k on the engine since installing it. Bought some plugs and 2 O2 sensors the other day, hope to install them today and see if that resolves this issue. But since it was very intermittent, will be hard to call it "good".

[cammed goat]

OK. Keep us posted.