Need your help guys. I'm getting a Check Engine Light on my 96 GSR engine. "CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD. MALFUNCTIONING OR DEFECTIVE CATALYST SYSTEM" I think it's because im running no CAT. Any ideas on how I can stop this?

 

get a cat

 

Either build one of these
http://www.jdmfan.com/technical/perf...sor_simulator/

or get a high flow cat

 

i had that code a while back....i think....something to do with the wiring of my 02 sensor....check the wiring, cuz sometimes the heatshields underneath snags the wires...

 

If I did the wiring on the O2 Sensor incorrectly, wouldn't it throw that CEL the first time i started the engine? Because it's been running fine with no CEL for about 3 weeks now.

 

If youa re running no CAT, then you are going to throw a CEL no matter if you wiring is correct. You ECU is reading the hydrocarbons too high from the secondary O2 sensor. Remember you are OBDII which means you have one O2 sensor in the exhaust, and one after the catalytic convertor, it is the second O2 sensor that is making you throw the code due to not have a cat. See about bulding that O2 sensor simulator I posted up, that will get rid of that CEL.

 

Please just put in a cat, make it a high flow, but put in a cat. The engineers at honda spent a lot of time to make that car run as efficiently and cleanly as possible, so for their sake and for everyone else's sake, run a cat, the gains are not worth the environmental losses. You will all probobaly call me a tree hugger now, but in 20 years when our children all have skin cancer, you'll run a cat.

-GSRacer