Dodge SRT Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
63 Posts
Discussion Starter · #1 ·
I'm thinking about a 3 inch catless exhaust, My question is will this cause a CEL? If it will how do I fix the problem? I've already tried a search and got alot hits but could find nothing useful...plus I'm stuck with 56k and theres only so much loading time I can take!
 

·
Registered
Joined
·
5,379 Posts
In most cases:
  • If you don't have stage 1 or 2, and remove the cat, you will get a cel
  • If you do have stage 1 or 2, and remove the cat, you won't get a cel
Some people have gotten lucky, and not gotten a cel even though they had no staged upgrades and removed the cat.

If you have stage 1 or 2, you still need to have the downstream O2 sensor (the one in the cat) hooked to the wiring harness. The pcm is still looking to see if the sensor is connected even though it's ignoring the sensors readings.
 

·
Registered
Joined
·
63 Posts
Discussion Starter · #4 ·
scottmech said:
In most cases:
  • If you don't have stage 1 or 2, and remove the cat, you will get a cel
  • If you do have stage 1 or 2, and remove the cat, you won't get a cel
Some people have gotten lucky, and not gotten a cel even though they had no staged upgrades and removed the cat.

If you have stage 1 or 2, you still need to have the downstream O2 sensor (the one in the cat) hooked to the wiring harness. The pcm is still looking to see if the sensor is connected even though it's ignoring sensors readings.
What do you mean by down stream the sensor?
And why does it matter if I have the s1 or s2?

This great info guys, Thanks a million! :thumbsup:
 

·
Registered
Joined
·
5,379 Posts
There's two O2 sensors in the emissions control system.

The first one (in the O2 housing located just after the exhaust manifold) moniters air fuel ratio. The pcm chages the a/f ratio based on this sensors readings during certain coditions.

"downstream" sensor means farther down the exhuast path. The second O2 sensor is located in the cat, or farther "downstream" from the first O2 sensor in the O2 housing.

Stage 1 and 2 are considered "off road use only" mdifications, therefore they do not have to meet emisions requirements. A common "off road" performance modification would be an exhaust without a cat, and the PCM's with stage 1 and 2 are calibrated so those modifications would not cause a cel.
 
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top