Chevy SSR Forum banner

1 - 17 of 17 Posts

·
Registered
Joined
·
678 Posts
Discussion Starter #1
03 with 85000 miles, stock with Joes tune.....looking for advice.
Check engine light came on, plugged in the code reader-P0420- Catalyst efficiency below threshold (bank one).
A little poking around on the internet says possibly a bad catalytic converter. So is it common for these go bad ?
Kind of a big deal out here on the left coast dealing with the smog nannies...........

Thanks Don J
 

·
One of the SoCal Nuts
Joined
·
27,660 Posts
03 with 85000 miles, stock with Joes tune.....looking for advice.
Check engine light came on, plugged in the code reader-P0420- Catalyst efficiency below threshold (bank one).
A little poking around on the internet says possibly a bad catalytic converter. So is it common for these go bad ?
Kind of a big deal out here on the left coast dealing with the smog nannies...........

Thanks Don J
  1. You might want to look here. I found that with a simple search of the error code.
 

·
Premium Member
Joined
·
2,306 Posts
Here in a non emissions testing zone i have heard of some having luck with a$20 O2 fooler. Search in Amazon or Ebay motors for more Information. It goes in between th he O2 sensor and the cat (the left one in your case). It does require some space though not sure if there is enough.
Also probably not legal in California. Actually probably not legal for street use anywhere in US. If you get caught?
Never tried it myself, like i said "I've heard ...."

Good luck

Go Bucks
 

·
SSR Pit Crew
Joined
·
12,015 Posts
I don't think it is converters I changed both catalectic oxygen sensors on my R.

One for IN and one for OUT, times 2 converters.

Also seen cracked plug send code.

Dicktator
 

·
Supporting SSR Hobbyist
Joined
·
9,696 Posts
There are 4 oxygen sensors in the exhaust. One upstream and one downstream of each converter. The two upstream sensors are used to optimize the fuel/air ratio settings in the engine computer. The two downstream sensors are used to validate “normal” operation of the converters to specs. If you are looking to try the easiest and simplest fix first, I would use the data you have and replace the downstream O2 sensor for bank one. As I remember, there are specific GM part numbers for each of the the O2 sensors...... may just be lead length.....

My two cents,

Mike
 

·
Cantankerous SSR CaretakR
Joined
·
2,243 Posts
Yes they are specific, either upstream (pre-converter) or downstream (post-converter), but same side to side (bank 1 & bank 2). If you decide to replace yourself, ck your connector. 2003 should have square connectors. Somewhere on '05-'06 they used some triangle (actually trapezoid) connectors. Dont let parts person give you wrong parts. Buy good quality...
 

·
Premium Member
Joined
·
2,306 Posts
Sorry, for some reason i thought you had replaced the downstrean O2 sensor already. Hard to tell with digital data - really need a lab scope to compare up stream to down stream scope patterns the down stream should be flatter that the upstream as the catalyst uses the oxygen to function.
To add to Mikes great description, bank one is always the same exhaust stream as cylinder one.

If you have to have emission test, or trying to see if it fixed it. It seems like getting the cat monitor to run is one of the hardest to run.

Also it is a 2 trip code ---- that means for light tom come on:
While driving if the self test for this code sets - it is stored as a pending code (no check engine light), the next time the self test runs (might not be the next time you drive it) if it fails again the code is stored and the light comes on, if it passes then pending code is erased.
for light to turn off it take 3 consecutive PASSES ( might not be 3 consecutive times you drive the car!) and then the light will turn off next time the car is started.

Why is this important -- Whatever you decide to do It may take some driving to turn light off indicating problem fixed -- or if you clear the computer it will take some time to ensure the problem went away.

I might try top off with fuel then clear the codes (pull fuses or disconnect battery) then drive for awhile to see if it comes back on, of course this is assuming you have time before your next E-Check. AND can get out and drive - it will require some higher steady speeds to run self test
 

·
Registered
Joined
·
678 Posts
Discussion Starter #10
Ya know, one can always count on the guys here on this site for some great advice!
The plan is new plugs and wires (85000 miles on the originals) and replace both upstream 02 sensors.......and I have noticed now a slightly rough idle, so basics first.

This home isolation does extend to the shop after all.......and this “social distancing” thing doesn’t include the dog, so I’ll be in good company!
 

·
Registered
Joined
·
162 Posts
The miles you stated & age of your SSR? The converters have burned catalytic out. The horrible blend of gasoline with 10% ethanol causes it. Crawl underneath SSR drivers side. Take hammer with you & tap the Cats. A rattling sound is all the platinum honey comb is disintegrating. If no sound? All the platinum is gone out tail pipe & may have clogged the tail pipes. No additive will fix the problem. I know from experience with my 04 SSR. Go to Magna flow to get replacements. Advance Auto parts has connection to order. Problem is only a few Exhausts for are made any more. I waited 2 years for Magna flow to make mine. I had to take to muffler shop to be installed. Replace all 4 O2 sensors. The change to a performance exhaust is felt right away. IMPORTANT!! Get a piece of exhaust blanket from DEI. I installed the 12 x 12 aluminum piece around the ABS module & Shifter linkage. Yeah, Mikes shield helps. It does not prevent heat soak that as all should know? Heat rises. The Catalytic converters reflect heat up to floor & a stick on aluminum back down to top of ABS module.
 

Attachments

·
Registered
Joined
·
162 Posts
Ya know, one can always count on the guys here on this site for some great advice!
The plan is new plugs and wires (85000 miles on the originals) and replace both upstream 02 sensors.......and I have noticed now a slightly rough idle, so basics first.

This home isolation does extend to the shop after all.......and this “social distancing” thing doesn’t include the dog, so I’ll be in good company!
Read my reply before wasting your money. Your Cats are gone & need replacement. I replaced mine at same mileage as your SSR
 

·
RetroCarGuy530
Joined
·
1,570 Posts
If you're replacing the O2 sensors, make sure you stick with ACDelco sensors since I recently had a problem with what were to be ACDelco O2 sensors, but in fact were not (eBay purchase gone wrong) and as a result the non ACDelco post cat O2 sensors generated new codes.

The part numbers are specific to the 2003/2004, 2005/early 2006 and then the post cat O2 sensors were changed to a triangle style connector during the 2006 model year.

I have a video talking about the O2 sensors with ACDelco part number info.

 

·
SSR Pit Crew
Joined
·
12,015 Posts
Usually it is sensors, of course FLORIDA has NO emission test!!!

I have 148,000 miles on my converters, Chuck has 206,000 on his.

Catalytic Converters are warrantied for 100,000 miles but they have a time limit.

Dicktator
 

·
SSR Pit Crew
Joined
·
12,015 Posts
If you're replacing the O2 sensors, make sure you stick with ACDelco sensors since I recently had a problem with what were to be ACDelco O2 sensors, but in fact were not (eBay purchase gone wrong) and as a result the non ACDelco post cat O2 sensors generated new codes.

The part numbers are specific to the 2003/2004, 2005/early 2006 and then the post cat O2 sensors were changed to a triangle style connector during the 2006 model year.

I have a video talking about the O2 sensors with ACDelco part number info.

Well done! This tells it all.

Dicktator
 

·
Supporting SSR Hobbyist
Joined
·
9,696 Posts
With all the above possibilities....... I would take a very measured approach. I don't like shotgun fixes.... they tend to create more problems than they solve. Change the downstream sensor on bank 1 (driver's side) first and then see if it clears the issue. The sensor prices out at about $35 on Amazon.

Helpful hints:
When removing the old sensor, it is easier when the exhaust system is hot.
Be sure to use anti-seize on the new sensor before installing it.
Be mindful of the cable routing and tie points so that you put the wiring back the way it should be....

My two cents,

Mike
 

·
_________________________
Joined
·
733 Posts
P0420Disable.jpg


With a custom exhaust, I kept getting this code on both sides (P0420, P0430). There are some posts elsewhere on the web that state that these can occur with High Flow Cats installed. I disabled the Error Reporting on it in the Tune and have never had another problem. It has gone through Phoenix area OBD II emissions tests 3 times since then with no issues.
 
1 - 17 of 17 Posts
Top