Im a bit confused here

The story is that I heard a rattle at idle so I attributed to the cat but the shields were on tight so I took my cat off and there it was, the honeycomb broke off its housing inside but the cat works otherwise.
has this happened to anybody yet?

so I decided to put my hollowed out cat on and I drove it all last night without CEL. I drive it today and while de-accelerating the CEL comes on.

I thought that people that ran test pipes would get the CEL because they didnt connect the secondary 02 sensor. But in my case I connected it and still got a CEL...??

 

my CEL came on with the O2 sensor pulled in.
you need a O2 simulator to eliminate the CEL or pull the backup fuse for a temp. fix

 

The DTC will be for "Catalyst below efficiency threshold" (P0420) In basic terms, the cat isn't working. The PCM monitors catalyst function through comparing primary and secondary 02 inputs. If you leave the secondary 02 out, the PCM throws a DTC for secondary 02 heater failure (P0141)

To prevent the P0420 you can use a 02 simulator, like the ECG 02 simulator. www.wiredspeed.com sells them for $45

To prevent the P0141, you can install the secondary 02, which I don't reccomend leaving the 02 under the car. Or you can use a 13ohm 10watt resistor wired into the heater circuit. Like this:

 

[QUOTE]Originally posted by Slows2k
The DTC will be for "Catalyst below efficiency threshold" (P0420) In basic terms, the cat isn't working. The PCM monitors catalyst function through comparing primary and secondary 02 inputs. If you leave the secondary 02 out, the PCM throws a DTC for secondary 02 heater failure (P0141)

 

If the Secondary 02 is plugged in, you won't have a DTC for the heater, you will get the DTC for the convertor not working though.

The 5 wire 02 sims have worked, mine has been going for 2 months without a problem.

 

[QUOTE]Originally posted by Slows2k
If the Secondary 02 is plugged in, you won't have a DTC for the heater, you will get the DTC for the convertor not working though.

 

http://www.wiredspeed.com/itemdesc.asp?ic=...2DO2SIM&eq=&Tp=

 

thanks very much!

 

hey man what year is your car im curios

i have an 02, and i just installed it and i get a CEL instant as soon as the car starts, dont know if its for something else, but all the wiring is fine, checked 2 or 3 times, and also found a write up by s2kevolution,and confirmed the wiring with my S manual and everyting is connected right. wish i had a scan tool to get CEL codes.

 

Do you have the 02 sensor installed? If the 02's heater is not in the circuit, a P0141 DTC will be thrown for heater failure.