im trying to get my 96 xj emissions ready as my registration is due for renewal. my scan tool checks for I/M readiness and i keep getting a yellow light. i code for random misfire and cylinder 6 misfire occasionally, which i will check but i can clear those temporarily if needed.
my problem is the oxygen, oxygen heated, and catalyst monitors keep reading "not ready". some times the first two go away but the catalyst monitor keeps flashing.

i have a borla header, new flowmaster cat and ran new 2.5" pipe all the way back. downsteam o2 is fairly new as well. i used to run straight pipe and never had an issues.
what should i be looking at to get these monitors running ?

 

IMO you could get it real hot and hope the carbon gets blown out. You could try to drive the mess out of it for about 15 mins before you get it tested. Not sure it that would help or not.

 

Removing carbon due to the misfire? Would a sea foam treatment work for that?

 

Check your plugs, wires, cap, and rotor.

 

Cap, rotor, plugs, and wires were all replaced within the past 6 months. I used the champion rc12y plugs, something like that. Whichever ones are stock recommended.