Tips for dealing with P0420/P0430 now P0139/P0159 after spacers (1 3/4" LT's w/ cats)

[16WhiteQC]

Long and short is I had no issues after the initial install of the ARH 1 3/4" with cats on the stock manifold custom tune, ran it for 3 months till my first P04xx code.

Cleared that and loaded up the header tune, ran good for a while but anywhere from 30 - 200+ miles later I would get the code(s), especially if it was "wet out".
Summer running the A/C seemed to go the longest without a code.

Recently installed some 90* spacers to deal with the P04xx codes and am now getting P0139/159 due to the sensors being out of the stream, FFS lol.

So, anyone have any tricks for trying to balance keeping the rear sensors "active" ? (for state inspection, plug in not actual sniffer)


"Active" = vs "not Ready" if you understand what I am saying without saying it.

*EDIT* - I have not done a reset to the PCM via disconnecting the negative yet, not sure if that will even do anything at this point.

 

[Brandon-w]

Just get Ur tuner to block the codes. If Ur using hp tuners and the tune isnt locked I could make it so that tune doesnt report and set off the light

 

[16WhiteQC]

Just get Ur tuner to block the codes. If Ur using hp tuners and the tune isnt locked I could make it so that tune doesnt report and set off the light

Appreciate it, currently on Diablo i3...in hindsight I should have gone HP!
I have an option, but I believe it just involves being "off".

If you block the codes with the 02's show "ready" or will there be a fault in the PCM?
(02's need to show "ready" in order to pass inspection from what I read)

 

[Sillygoose]

i think if you turn off the rear o2's in the tune it will never show as ready, possibly for both o2 and cat monitors. you are entering Leeroy territory issues lol

 

[Brandon-w]

Oh yeah I can't tune for diablo. You can stuff a bit if steel wool in the spacers if you're getting the I effecient codes that helps too. I don't lave any emissions worries out here so I don't have cats

 

[Wild one]

Appreciate it, currently on Diablo i3...in hindsight I should have gone HP!
I have an option, but I believe it just involves being "off".

If you block the codes with the 02's show "ready" or will there be a fault in the PCM?
(02's need to show "ready" in order to pass inspection from what I read)

O2 Simulator Mini Cat Cel Fix stainless steel Rear O2 sensor simulator.

O2 Simulator Mini Cat Cel Fix, Big Daddies Garage Mini Catalytic Convertor Rear Oxygen Sensor Simulator is the best and easiestway to clear p0420 / p0430 codes for bad or missing catalytic converters. Just screw it the o2 simulator mini cat into the existing exhaust then srew in the oxygen...

www.bigdaddiesgarage.com

 

[16WhiteQC]

O2 Simulator Mini Cat Cel Fix stainless steel Rear O2 sensor simulator.

O2 Simulator Mini Cat Cel Fix, Big Daddies Garage Mini Catalytic Convertor Rear Oxygen Sensor Simulator is the best and easiestway to clear p0420 / p0430 codes for bad or missing catalytic converters. Just screw it the o2 simulator mini cat into the existing exhaust then srew in the oxygen...

www.bigdaddiesgarage.com

I have their 90*s which solved the P0420/30...but now have the p0139/59.

I.E. the cat ones probable won't work either.

 

[Wild one]

I have their 90*s which solved the P0420/30...but now have the p0139/59.

I.E. the cat ones probable won't work either.

Wonder if swapping to their straight ones would work.

 

[Burla]

go back to w/o spacers and try some cat cleaners just to pass inspection? I cant believe the emmision cops beat the spacers

 

[Burla]

CATACLEAN Catalytic Converter Cleaner | Does It work?! (Real Data) Before And After

Today we put cataclean catalytic converter cleaner to the test! We have a bmw car in the shop that has an engine light that needs fixed p420 p430 p431. Thank...

youtu.be

 

[16WhiteQC]

Pulled the spacers Sat. after getting a bunch of faults including P0139, p0159, p2271 & p2273.

Decided to run the truck after removal and was able to rack up 170+ miles of hot rodding, sustained highway, sustained backroad driving before P0420 popped.

Here is my theory on this.

1. I am not getting the cat's hot enough on my daily commute/just "putting" around.

2. If I rip on the truck, do sustained highway driving, or use the truck as a truck to haul/tow then I don't seem to get any p0420/30 codes.

3. These are high flow cat's that just don't get hot enough to function close enough to the factory parameters without some sort of load on them.

4. When it is time for inspection I will flash back to "stock" tune, hook up and tow around my trailer to get the monitors ready.

This comes from thinking back and realizing I have never gotten a code on the highway or while towing. It only seems to pops under low load cruising.

 

[Burla]

See the tubes on the cat cleaners, in theory it will end the entire problem not just when you are on freeway. You could probably even shoot some type of cleaner in the spacer hole. I'm sure you are correct in what's happening, but because it got so bad you likely need to clean all the edges etc. It would be cheaper then spending it on gas and running for 200 miles, but of course less fun.

Now I wonder if sea foam would clean this


.

 

[DILLIGAF]

You need a custom tune, no other way around it. All of those o2 spacers are just a Band-Aid.

 

[pacofortacos]

I have their 90*s which solved the P0420/30...but now have the p0139/59.

I.E. the cat ones probable won't work either.

The cat versions do work, used them with a hollowed cat and never got any code - for years on a 5.9 dakota with Cali emissions package on it.
I used the straight cat versions - the ones Wild one referenced.

 

[16WhiteQC]

You need a custom tune, no other way around it. All of those o2 spacers are just a Band-Aid.

I can neither deny or confirm that I have a tune that takes care of the rear 02's

 

[DILLIGAF]

Run some live data scans, and see what's going on when the CEL gets triggered.

Heck my 02 codes I was chasing after my 8 speed swap was a bad connection.

 

[Lloyd33]

Run some live data scans, and see what's going on when the CEL gets triggered.

Heck my 02 codes I was chasing after my 8 speed swap was a bad connection.

Even though I read through this entire thread about O2 sensors, for some reason when I got to this I thought you meant that you meant your '02 (as in 2002) had an 8-speed swap and I got *super excited* there for a second!!

 

[16WhiteQC]

Since my truck is now strictly a "race truck" I tried a set of these and they seem to have resolved 95% of my issue. - http://www.bigdaddiesgarage.com/straight-cel-fix.html

I do still get an intermittent "slow response" CEL, but it's not as often as the CEL's previously.

 

[RedSRT4Me]

Long and short is I had no issues after the initial install of the ARH 1 3/4" with cats on the stock manifold custom tune, ran it for 3 months till my first P04xx code.

Cleared that and loaded up the header tune, ran good for a while but anywhere from 30 - 200+ miles later I would get the code(s), especially if it was "wet out".
Summer running the A/C seemed to go the longest without a code.

Recently installed some 90* spacers to deal with the P04xx codes and am now getting P0139/159 due to the sensors being out of the stream, FFS lol.

So, anyone have any tricks for trying to balance keeping the rear sensors "active" ? (for state inspection, plug in not actual sniffer)


"Active" = vs "not Ready" if you understand what I am saying without saying it.

*EDIT* - I have not done a reset to the PCM via disconnecting the negative yet, not sure if that will even do anything at this point.

I just went through this. The trick is once you reset the PCM to clear pending codes (no permanent) install the spacers and when you drive you have to throttle your speed constantly up and down to get the voltage too move quicker. It's an absolute pain but that is how I did it. Once you pass the emissions ready portion get it to the testing center asap.

 

[RedSRT4Me]

Just get Ur tuner to block the codes. If Ur using hp tuners and the tune isnt locked I could make it so that tune doesnt report and set off the light

This doesn't work in some states. The catalyst and O2 sensor portion will report as not ready for testing which is an automatic fail