I had just fixed the O2 sensor in my 98 Neon R/T, seems that the vibrations rubbed the wires raw and they came apart, so I fixed them and got the CEL to go off, got my fuel economy back too!

Here is my problem.. I was driving around tonight with a few friends, coming back from out of town and my CEL light turns back on, I am like WTF by this point, very aggrevated with this light.. So I get home and do the OBD and it gives me 1 - 2 - 7 - 2 - 5 - 5... 12, 72, 55...

I cannot find ANYWHERE that says anything about a code 72.. I have been having a cooling problem with this car lately, and yesterday, it rocketed up to HOT and binged at me, shut the car off immediately sat for a minute at the red light and turned it back on, the temp was back down to normal.. I am completely stumped with this and I have no idea where else to look... Can someone PUHLEASE help me!

 

as far as the heat coming down that fast, sounds like you might have air in the system, as far as the code goes take it to auto zone or what part stor you have around there and have them trow it on there scaner, most will do it for free as i've never heard of code 72

 

Code 72 is...catalytic converter effenceny below standard! Replace your cat.