The dreaded P0420 code

[PeteyDaMan]

So....
My 07 Charger R/T shot a P0420 code at me 2 months ago. It has 260,000 miles on it and I've taken obsessive levels of care with it since new. At the time I bought it Chrysler was offering a life time bumper to bumper warranty which I happily purchased.
This car has given so few issues over the past 15 years until now.
For those that don't know, P0420 means the catalytic converter isn't performing to spec.
I took it to the stealership figuring it would be covered by the warranty....WRONG!!!! They say exhaust components aren't covered. To me it's emissions, not exhaust. They give me a quote of over $5000 to replace both cats and O2 sensors....f**k!!
I live in PRNY ( peoples republic of NY) and our cars have to meet California emissions (CARB) so the cats are twice the cost of the rest of the country. Double f**k!!!
So....I hop on the ol' interwebs to see what options I have. A lot of folks have had success putting spacers in the down stream O2 sensors to trick the PCM. So I put spacers in the down stream sensors, clear codes and go for a drive cycle......50 miles later...Bing!!! P0420.....F**k yet again!!.
OK, I look at the O2 sensor voltages and they look fine to me but maybe there's an exhaust leak or the downstream sensors are bad. 2 new downstream sensors and 50 miles later...Bing!! P0420. How many times can I say F**k????
Hail Mary time and I go for the bank 1 upstream O2 sensor.
. DAMN! That thing is a bit*h to get to. After much cursing and scraped up arms I get the old one out. Houston, I think I found the problem.
I'll let you know in 50 miles...

 

[YY1]

What? You didn't just give them the 5 grand?

 

[Bighouse]

O2 Simulator Dodge Challenger Charger High Performance Cel Fix.

 

[padam]

I had that on Lexus recently. The short straight spacers didn’t work. Had to put 90 degree spacers (big daddies garage, no not THAT big.)
They worked, car runs fine , no codes couple thousand miles.

Edit: same site as previous post

 

[Jim 68cuda]

Hope the problem is solved. I have a 2014 Challenger RT. If I neglect to pull my car into the garage when I get home, groundhogs will eat the wiring for my O2 sensors. Happened twice. Critters won't leave the car alone. Once a few months ago, I started the car (after leaving it parked in the driveway for an hour) and one of two that were under the hood at the time, caused the serpentine belt to come off. Next time you replace the O2 sensors, check to see if the wiring has teeth marks.

 

[padam]

Also, if you can look at live data on a scanner, the downstream O2 sensors should be more of a flat line. If they match the upstream pattern (wavy) the cats are most likely bad.

 

[Nxcoupe]

Petey, I can check to verify if the dealer was correct in telling you the warranty didn't cover it if you'd like. Just PM me the last 8 of your VIN and I can pull your coverage up and get with a coworker to fimd out.

 

[Lefty71]

Rootin for not against ya.....but isn't that upstream O2 sensor so baked because the converters are plugged enough to cause high temps and fry it??

 

[Gus chiggins]

So....
My 07 Charger R/T shot a P0420 code at me 2 months ago. It has 260,000 miles on it and I've taken obsessive levels of care with it since new. At the time I bought it Chrysler was offering a life time bumper to bumper warranty which I happily purchased.
This car has given so few issues over the past 15 years until now.
For those that don't know, P0420 means the catalytic converter isn't performing to spec.
I took it to the stealership figuring it would be covered by the warranty....WRONG!!!! They say exhaust components aren't covered. To me it's emissions, not exhaust. They give me a quote of over $5000 to replace both cats and O2 sensors....f**k!!
I live in PRNY ( peoples republic of NY) and our cars have to meet California emissions (CARB) so the cats are twice the cost of the rest of the country. Double f**k!!!
So....I hop on the ol' interwebs to see what options I have. A lot of folks have had success putting spacers in the down stream O2 sensors to trick the PCM. So I put spacers in the down stream sensors, clear codes and go for a drive cycle......50 miles later...Bing!!! P0420.....F**k yet again!!.
OK, I look at the O2 sensor voltages and they look fine to me but maybe there's an exhaust leak or the downstream sensors are bad. 2 new downstream sensors and 50 miles later...Bing!! P0420. How many times can I say F**k????
Hail Mary time and I go for the bank 1 upstream O2 sensor.
. DAMN! That thing is a bit*h to get to. After much cursing and scraped up arms I get the old one out. Houston, I think I found the problem.
I'll let you know in 50 miles...

View attachment 1372153

I have a 2011 Dodge Charger RT. The center stack went out, and would keep discharging the battery because the radio would cycle on even when the car was off. Now my hands free bluetooth module went out causing the same problem. I cannot understand why these cars have to have phone connectivity. More bullshit electronic crap. Btw my car only has sixty six thousand miles. I'm seriously considering dumping this car, and get a decommissioned ford crown vic cop car, not as fast, but i don't care, at least i won't be replacing idiotic electronic stuff all the time.

 

[PeteyDaMan]

Live scanner data shows a dramatic difference between the upstream and down stream sensors. up is switching fairly rapidly and down is mostly flat.

The converters aren't plugged. No loss in performance or fuel mileage.

If I continue to have issues I'll get the angled spacers

 

[padam]

Live scanner data shows a dramatic difference between the upstream and down stream sensors. up is switching fairly rapidly and down is mostly flat.

The converters aren't plugged. No loss in performance or fuel mileage.

If I continue to have issues I'll get the angled spacers

If the downstream is flat I don’t think the spacers will be the fix.
Also the cats are probably ok.
My advice would be to get the troubleshooting chart for your car and see what else it might be.

 

[toolmanmike]

So....
My 07 Charger R/T shot a P0420 code at me 2 months ago. It has 260,000 miles on it and I've taken obsessive levels of care with it since new. At the time I bought it Chrysler was offering a life time bumper to bumper warranty which I happily purchased.
This car has given so few issues over the past 15 years until now.
For those that don't know, P0420 means the catalytic converter isn't performing to spec.
I took it to the stealership figuring it would be covered by the warranty....WRONG!!!! They say exhaust components aren't covered. To me it's emissions, not exhaust. They give me a quote of over $5000 to replace both cats and O2 sensors....f**k!!
I live in PRNY ( peoples republic of NY) and our cars have to meet California emissions (CARB) so the cats are twice the cost of the rest of the country. Double f**k!!!
So....I hop on the ol' interwebs to see what options I have. A lot of folks have had success putting spacers in the down stream O2 sensors to trick the PCM. So I put spacers in the down stream sensors, clear codes and go for a drive cycle......50 miles later...Bing!!! P0420.....F**k yet again!!.
OK, I look at the O2 sensor voltages and they look fine to me but maybe there's an exhaust leak or the downstream sensors are bad. 2 new downstream sensors and 50 miles later...Bing!! P0420. How many times can I say F**k????
Hail Mary time and I go for the bank 1 upstream O2 sensor.
. DAMN! That thing is a bit*h to get to. After much cursing and scraped up arms I get the old one out. Houston, I think I found the problem.
I'll let you know in 50 miles...

View attachment 1372153

Try again. Convertors are Emission and should be at least 5 yr/50,000 miles. WHen I worked at the GM store, spark plugs were even emission covered.

 

[Cranky]

Try again. Convertors are Emission and should be at least 5 yr/50,000 miles. WHen I worked at the GM store, spark plugs were even emission covered.

IIRC, the fed requires the warranty on emissions equipment is longer than 5/50. Think it's more like 7/70 or more. I got a new cat from the dealer on my 95 Dakota years ago and it was more than 5 years old at the time. Thing is there wasn't anything wrong with the cat. The morons at the inspection station ran the thing hot on the dyno and the NOX numbers went through roof. When I finally started watching (they were taking a really long time to run it) I noticed they didn't have a fan in front of it so I went out into the shop to look at the temp and it was almost pegged. Talk about pissed!! And that test was with the new cat and the NOX was still high. Cats don't reduce NOX that much....at least not for an engine that's running high temps. The gauge was nearly pegged. This is where I learned a cooler running engine produces lower NOX numbers.

 

[PeteyDaMan]

Good News!! After a nice long drive yesterday the CEL went our an no more P0420!!!

My car is 15 years old and has over 260,000 miles so the factory emissions warranty is long gone.

As for my extended warranty, I did call the Chrysler extended protection office and they confirmed that the cats are not covered by my lifetime bumper to bumper.

 

[padam]

Good News!! After a nice long drive yesterday the CEL went our an no more P0420!!!

My car is 15 years old and has over 260,000 miles so the factory emissions warranty is long gone.

As for my extended warranty, I did call the Chrysler extended protection office and they confirmed that the cats are not covered by my lifetime bumper to bumper.

“Bumper to minus a few things bumper “ I guess

 

[69a100]

It seems now days with these newer vehicles that if you have a maintenance issues, don't look at the car, look at the sensors for your problem. Glad it's fixed.

 

[moparedtn]

It seems now days with these newer vehicles that if you have a maintenance issues, don't look at the car, look at the sensors for your problem. Glad it's fixed.

Heck, that was true on my '85 I bought new. Damn thing ate sensors like candy....every damn month.
('85 GLH Turbo).
When it ran out of warranty (and the transaxle got replaced under warranty), I got rid of that thing so damn
quick....and bought a Ford.
Yes, a 5.0 Mustang, which proceeded to go 250k miles without a single electronic or sensor failure (despite
me racing it and beating on it like a rented mule constantly).

If the OP was NOT in commieNY, I'd be recommending O2 emulators in a slap hurry....

 

[69a100]

It seems now days with these newer vehicles that if you have a maintenance issues, don't look at the car, look at the sensors for your problem. Glad it's fixed.

And here we go as I now have problems; did I curse myself?? Dealing with a 94 Caravan w/a 3.3
I had to get a tow home yesterday as the vehicle died! And I mean DEAD!
I got the following codes last night after getting home. Not enough juice to start it but enough to do a code test.
MAP Sensor electrical failure
MAP Sensor pneumatic failure
Vehicle speed sensor circuit
Loss of Batt. voltage - I'm at a loss as to what this is???
Would a healthy charging system show good if a batt. won't charge?
This morning it started but with an old/dead batt. type condition, code check came up clean.
Did the system re-set itself overnight?
I hate dealing with electronics!

 

[4406bbl]

Those year vans have an issue with grounds. There is a main ground on a stud under the battery tray that is painted during assembly, they then rely on a paint cutter terminal and nut to make the ground. It kills the van dead. First thing I would do is clean every ground you can find and buy a new battery.

 

[padam]

Disconnecting the battery will clear the codes.
Get the battery and charging system right then go from there