Cleaned Out My Catalytic Converters now runs way too rich???

**Rogernstjoe** · 01-30-2011, 10:47 AM

Had my Cats cleaned out a couple days ago. Before it was running good but lacking performance for an LS1. Since cleaned out my check engine light came on and now the motor is running way too rich. Smokes black when I get into it from a stop, motor faulters when driving a constant speed and it smells like gas. What do I need to do? Thank you

**ls1ws6ben** · 01-30-2011, 11:04 AM

if you dont have emissions testing where you live, just cut them off..thats what i did

**Rogernstjoe** · 01-30-2011, 02:39 PM

Your answer shows you didn't read my problem. Thanks anyway!

**ls1ws6ben** · 01-30-2011, 02:56 PM

no i did read it.. my were clogged and i just cut them off.. getting LTs put on next month and a tune and delete the rear 02 sensors..after i cut mine off, it ran much better, yes the SES light is on, but my front 02s are shot but i can live with that for a month.. truthfully, if runs and definately sounds better since i got rid of them.. you may have had them cleaned but that doesnt mean your 02 sensors are good.. if you want to keep cats on there, get some magnaflow highflow cats and new 02s..

**shady milkman** · 01-30-2011, 03:19 PM

well you need to get a tune. you have a ses light because your rear O2s are reading a lot more air and the pcm still believes you have cats and the readings are outside the range.. you really should have done some research before gutting your cats..the power that could be gained is very little compared to the money you will have to spend

**0rion** · 01-30-2011, 05:31 PM

Originally Posted by shady milkman

well you need to get a tune. you have a ses light because your rear O2s are reading a lot more air and the pcm still believes you have cats and the readings are outside the range.. you really should have done some research before gutting your cats..the power that could be gained is very little compared to the money you will have to spend

rear O2's only verify the cats are working...the front O2's control fueling.

I would say yoru SES light is due to the cats being removed but you would need to get the codes read to be sure. Any way something got fubar'd forward of the cats? Also, without cats you're going to get a little more shit blowing through the exhaust so what you're seeing could just be normal. The only way to know for sure what you're fueling is doing is to log the car preferably with a wideband.

**Rogernstjoe** · 02-06-2011, 05:23 AM

UPDATE: Thank you for all the help. Now for the repair was as simple as disconnected the ground cable on the battery, turned on the headlights while disconnected to drain all electricity from the elctrical system. Waited about an hour. Reconnected the battery, started the car and took it for a drive. So far the check engine light is still off and the computer must have reset and now it is running good again. Best of all, No additional expenses.

**shady milkman** · 02-06-2011, 07:18 AM

Originally Posted by shady milkman

well you need to get a tune. you have a ses light because your rear O2s are reading a lot more air and the pcm still believes you have cats and the readings are outside the range.. you really should have done some research before gutting your cats..the power that could be gained is very little compared to the money you will have to spend

Originally Posted by 0rion

rear O2's only verify the cats are working...the front O2's control fueling.

I would say yoru SES light is due to the cats being removed but you would need to get the codes read to be sure. Any way something got fubar'd forward of the cats? Also, without cats you're going to get a little more shit blowing through the exhaust so what you're seeing could just be normal. The only way to know for sure what you're fueling is doing is to log the car preferably with a wideband.

i know..but O2 sensors still read the same...front or back..so when the rears' readings are out of range from where the pcm things they will be..it will trip a SES ........that was all i was saying

**shady milkman** · 02-06-2011, 07:19 AM

Originally Posted by Rogernstjoe

UPDATE: Thank you for all the help. Now for the repair was as simple as disconnected the ground cable on the battery, turned on the headlights while disconnected to drain all electricity from the elctrical system. Waited about an hour. Reconnected the battery, started the car and took it for a drive. So far the check engine light is still off and the computer must have reset and now it is running good again. Best of all, No additional expenses.

all you did was clear the trims and the code temporarily ...you will get the low efficiency code again.

**Rogernstjoe** · 02-06-2011, 08:09 PM

Feb 6th, 2011
I have driven my TA several hours since I unhooked my battery and cleared the code(s). The car is still running great and the check engine light hasn't stayed on again. The light came on and stayed on within 5 minutes of getting my cats cleaned out. So far so good. And again, no additional expenses.

**bluehawk2000** · 02-06-2011, 09:54 PM

It will end up throwing the same code here soon trust me, you have to have your car tuned for it!!

**Spaz** · 02-08-2011, 05:55 AM

Originally Posted by bluehawk2000

It will end up throwing the same code here soon trust me, you have to have your car tuned for it!!

this...

**Rogernstjoe** · 02-09-2011, 08:32 AM

darn the luck.. LOL My check engine light came back on and now it's running too rich again. Is there a front sensor by-pass or something aftermarket to make my LS1 run with one O2 Sensor on each side? and! Who would I find to do a tune with my cats cleaned out? The check engine light wasn't on until I cleaned out my cats so I would think my O2 sensors were ok.

**shady milkman** · 02-09-2011, 08:38 AM

Originally Posted by Rogernstjoe

darn the luck.. LOL My check engine light came back on and now it's running too rich again. Is there a front sensor by-pass or something aftermarket to make my LS1 run with one O2 Sensor on each side? and! Who would I find to do a tune with my cats cleaned out? The check engine light wasn't on until I cleaned out my cats so I would think my O2 sensors were ok.

Pm frost..the best tuner you can find.

..after the tune you don't need to worry about the rears..and you get some power out of the tune too