CEL:P0420 & P0420pd? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

xpanda305x · 07-17-2011, 06:03 PM

i know the meaning

"The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system."

but i searched up on here and its to the people with headers and hi flow cats....well i dont have either! i have intake , mrt1.0 axle back and Resonator delete! how can i be getting this light? any help?

PoorMansCamaro · 07-17-2011, 06:17 PM

I would disconnect the battery for 5 minutes and see if the light comes back on b

xpanda305x · 07-17-2011, 06:29 PM

well i have done that. and it goes away or if i clear it. but in the long run it comes back! >.< i have done this like 2 or 3 times already!

MagnumForceGB · 07-17-2011, 06:34 PM

Warranty or sounds like a good excuse to buy long tubes and a tune.

usa1camaro1969 · 07-17-2011, 08:28 PM

Have you looked to make sure everything is still tight and no exhaust leaks anywhere?

PieNsky · 07-17-2011, 10:42 PM

I don't know for certain, however it seems as that is both banks.

montreal2010yellow · 07-18-2011, 06:42 AM

Which intake do you have?

I installed K&N 63 serie twice and had a CEL I could'nt get rid of.

Could be coming from the MAF also. Check this site for bad MAF with single number and single letter models that could be the trouble for your intake.

Might not be coming from your exhaust mods....CAI could be the problem.

PS When insalling a CAI battery has to be disconnected and not reconnected before the MAF is put back on the CAI. Doing a fuse pull for no5 and no20 fuses while the battery is disconnect could help also.

xpanda305x · 07-18-2011, 05:44 PM

well i do have the black tubing K&N intake? could that be it. it just came back today!

07-17-2011, 06:03 PM	#1
xpanda305x Banned Drives: Dark Knight Join Date: Nov 2009 Location: Gunshine State Posts: 3,150 View My Garage	CEL:P0420 & P0420pd? i know the meaning "The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system." but i searched up on here and its to the people with headers and hi flow cats....well i dont have either! i have intake , mrt1.0 axle back and Resonator delete! how can i be getting this light? any help?

07-17-2011, 06:17 PM	#2
PoorMansCamaro Drives: Really Slow Join Date: Apr 2010 Location: PA Posts: 56,957	I would disconnect the battery for 5 minutes and see if the light comes back on b __________________

07-17-2011, 06:34 PM	#4
MagnumForceGB Drives: Fastest 2010 Camaro V6 Join Date: Apr 2010 Location: Newcastle, OK Posts: 3,571 View My Garage	Warranty or sounds like a good excuse to buy long tubes and a tune. __________________ Camaro V6 = 11.268 @ 120.11

07-17-2011, 08:28 PM	#5
usa1camaro1969 Back on the dino-juice Drives: '10 LS + a few more Join Date: May 2010 Location: Texas Posts: 1,641	Have you looked to make sure everything is still tight and no exhaust leaks anywhere? __________________ I wake up in the morning and I piss excellence. -Ricky Bobby America is all about speed. Hot, nasty, badass speed. -Eleanor Roosevelt, 1936

07-18-2011, 06:42 AM	#7
montreal2010yellow Drives: 2 LT/RS YELLOW, AUTO., VIN NO. 602 Join Date: May 2010 Location: LAVAL (10 min. north of Montreal), CANADA Posts: 3,526 View My Garage	Which intake do you have? I installed K&N 63 serie twice and had a CEL I could'nt get rid of. Could be coming from the MAF also. Check this site for bad MAF with single number and single letter models that could be the trouble for your intake. Might not be coming from your exhaust mods....CAI could be the problem. PS When insalling a CAI battery has to be disconnected and not reconnected before the MAF is put back on the CAI. Doing a fuse pull for no5 and no20 fuses while the battery is disconnect could help also. __________________ T2 Facia, ACS TL1 Hood, ACS Winglets. G5CR CAI. Hotchsic Strut Brace and more...

07-17-2011, 06:29 PM	#3
xpanda305x Banned Drives: Dark Knight Join Date: Nov 2009 Location: Gunshine State Posts: 3,150 View My Garage	well i have done that. and it goes away or if i clear it. but in the long run it comes back! >.< i have done this like 2 or 3 times already!

07-17-2011, 10:42 PM	#6
PieNsky Drives: Victory Red 1LS Join Date: Nov 2008 Location: Louisville,KY Posts: 1,929 View My Garage	I don't know for certain, however it seems as that is both banks.

07-18-2011, 05:44 PM	#8
xpanda305x Banned Drives: Dark Knight Join Date: Nov 2009 Location: Gunshine State Posts: 3,150 View My Garage	well i do have the black tubing K&N intake? could that be it. it just came back today!