service engine light code

**RYDER661** · 04-05-2006, 06:39 PM

someone please help and tell me what is wrong with my car od2 code is
PO420 it shows up ywice... it says catalyst low flow restricted or sumthing like that does that mean my damn catalytic converter is out? also i have the flowmaster 80 series crossflow could this have caused this?

**SeVeReDiStOrTiOn** · 04-05-2006, 09:29 PM

cat efficiency below threshold....your driverside cat isn't working as good as it should. I had that code and I replaced the cats and haven't had the code in 4 months...before that it would pop up within a day of being cleared. Make sure the cat went bad on it's own though....because other conditions can cause a cat to go bad...like a blown headgasket or running rich. You want to fix the cause...not the effect, otherwise you'll be buying more then just 2 cats

**0rion** · 04-05-2006, 09:52 PM

First I would swap the rear O2 sensors to see if the code follows that sensor before changing cats. May just be a bad sensor but that's one way to find out. If it's the sensor it'll throw p0430 for the passenger side and if you still get 420 then it's time for new cats.

pontiac_god · 04-06-2006, 05:58 AM

Originally Posted by RYDER661

does that mean my damn catalytic converter is out?

Yep...for that bank. If it were an O2 sensor then you would throw a code PO13*.

**2001NBMZ28** · 04-06-2006, 10:09 AM

Don't forget about the federal emissions warranty on the cats - most of them get replaced free.

**keliente** · 04-06-2006, 11:36 AM

Originally Posted by 2001NBMZ28

Don't forget about the federal emissions warranty on the cats - most of them get replaced free.

8 years/80k miles. Some dealers will make exceptions, but don't expect it.

**RYDER661** · 04-06-2006, 12:32 PM

i bought my car used at 58,000 miles has 63k now does it still have the federal emissions warranty?

**2001NBMZ28** · 04-06-2006, 01:38 PM

Yep, the 8/80 is for the cats and PCM - don't have to be the original owner. Leave the light on and see what the dealer says - most will tell you over the phone diag fee, could be an 02, exhaust leak, physical damage to cat etc. - but I have a couple friends that had the same code and they replaced it free - only issue they had was P0420 illuminated.

**everett** · 04-07-2006, 08:14 AM

yeh i'd change the o2's first

**92ZZ3RS** · 04-07-2006, 06:29 PM

p0420 does mean the converters need to be replaced

**GLUMAKER** · 04-07-2006, 10:23 PM

I've had this code a few times and have thought nothing of it because I knew what the code meant. Is there any reason to replace my cats besides emissions compliance?

**SeVeReDiStOrTiOn** · 04-08-2006, 12:42 PM

Originally Posted by GLUMAKER

I've had this code a few times and have thought nothing of it because I knew what the code meant. Is there any reason to replace my cats besides emissions compliance?

If you don't want to replace them...either gut them or remove them....last thing that you want is a clogged cat.

pontiac_god · 04-09-2006, 06:34 AM

Originally Posted by SeVeReDiStOrTiOn

If you don't want to replace them...either gut them or remove them....last thing that you want is a clogged cat.

He doesn't have a clogged cat. You'll throw a PO420 for much less a problem than a clogged catalytic converter. It is an effeciency monitoring system that compares the voltage waveform of the upstream O2 sensor to the downstream O2 sensor. If you gut or remove the cat, you'd best not live where you are going to need to emission test because you will be driving with the SES light.

Just take it to the dealership and have them replace it. It's convered under warranty. They might be relanctant to do it...but still to your guns about it and you'll get a new one.

**jimbo4069** · 04-09-2006, 03:52 PM

I have a 2000 Chevy 6.0. It has dual exhaust straightpipes. My O2 sensor burns out when i put a new one in it. Where can I get the dummy sensor to put in for it?

**SeVeReDiStOrTiOn** · 04-09-2006, 07:30 PM

Originally Posted by pontiac_god

He doesn't have a clogged cat. You'll throw a PO420 for much less a problem than a clogged catalytic converter. It is an effeciency monitoring system that compares the voltage waveform of the upstream O2 sensor to the downstream O2 sensor. If you gut or remove the cat, you'd best not live where you are going to need to emission test because you will be driving with the SES light.

Just take it to the dealership and have them replace it. It's convered under warranty. They might be relanctant to do it...but still to your guns about it and you'll get a new one.

Yes I know it'll throw a code just for low efficency...like I said I had the same code and passed cali smog only a month before the p0420 started popping up. Also I never said he has a clogged cat...I said the last thing he wants is one....since it sounds like he planning on just leaving the cat the way it is.

And yes you can gut or remove the cats without having the ses on all the time....either get rear o2 sims or have the rear o2's tuned out.

**SeVeReDiStOrTiOn** · 04-09-2006, 07:33 PM

Originally Posted by pontiac_god

.
Just take it to the dealership and have them replace it. It's convered under warranty. They might be relanctant to do it...but still to your guns about it and you'll get a new one.

Also he lives in cali....so the cat warranty is only good for 7yrs/70,000miles....rest of the states it's 8yrs/80,000

**GLUMAKER** · 04-10-2006, 01:32 PM

Yes, I do plan on leaving the cat the way it is. I'll change it when I have to deal with smog.

**2001NBMZ28** · 04-10-2006, 02:32 PM

Originally Posted by jimbo4069

I have a 2000 Chevy 6.0. It has dual exhaust straightpipes. My O2 sensor burns out when i put a new one in it. Where can I get the dummy sensor to put in for it?

Assuming you have precat and post cat 02's like we do stock, 02 sims will work for the post cat sensors - if it's a front one something else is going on and sims won't work.