Code 420

[ViperGTS]

On the way back from Italy the check engine light came on and the code is 420.

"Catalyst bank 1 not working effective..."

Could be bad fuel ? Or a damaged cat?

Metal cats are in for 15000 miles. Corsa cat back.

Otherwise the car runs fine.

Tomorrow, I will see the dealer to check it out.

 

[RTTTTed]

Probably one of the O2 sensors?

Ted

 

[ViperGTS]

Yeah, was also an idea I had already...

 

[fqberful]

High flow cats can cause this issue. You can try a sensor or just use a SIMM to replace the downstream O2 sensor and never worry about it again.

Make very sure you inspect the wiring to the O2 sensor for burns and abrasions.

 

[Asp Man]

420? Thought maybe your car was a hippy or something.
(Maybe "420" doesn't mean there what it does over here.)

 

[crazyspeed]

Probably one of the O2 sensors?

Ted

Nope, it's the Cat

 

[crazyspeed]

Make very sure you inspect the wiring to the O2 sensor for burns and abrasions.[/quote]


uh uh It's the cat...... Ifn it was the O2...you'd get an O2 code...not a cat code

 

[Parisianviper]

Hello Markus,

I had a P432 code on mine (same code but passenger side) simply due to an exhaust leak. Just take off the side sills and check for leaks on the driver's side.

 

[fqberful]

uh uh It's the cat...... Ifn it was the O2...you'd get an O2 code...not a cat code

D00d, that code is caused by readings from the post cat O2 sensor. This is exactly what that sensor is there for. Try reading the FSM sometime.

 

[ViperGTS]

Erased the code and drove the car - did not come back, the check engine light. HF cats might cause the code alone from being hit by water...cooling down the cats fast makes them work less effective and we drove a lot in the rain during the recent Italy tour - so far o.k. ....but, I got another problem.

Checking the car out we found that the oil pan gasket is leaking....another 2-3 days to get the gasket and replace the leaking one!

 

[Warfang]

420? Thought maybe your car was a hippy or something.
(Maybe "420" doesn't mean there what it does over here.)

I was thinking the same thing!

 

[crazyspeed]

D00d, that code is caused by readings from the post cat O2 sensor. This is exactly what that sensor is there for. Try reading the FSM sometime.

That P0420 code means that the rear ( downstream ) 02 sensor is working fine but reads the same as the upstream 02 sensor...meaning there is a problem in the gas sample...NOT the O2 sensors..

BTW I don't have to read the FSM... I wrote it!!!!???