So tired of having a CEL... so, I've been on a mission to figure out the right combination to trick the ECU into working. Can't seem to find it...thus asking for help.

First, some background:
it's a 2004.
I use to just keep the OEM cat, until the element got loose and rattles.
I then ran just a test pipe, until every racing body I compete in requires a cat or it adds points.
So, I got a Berk HFC 70mm with the CEL fix.
I also have a code reader that I've been using to trouble-shoot.

Setup 1: OEM cat.
Result: No CEL. Full readiness for smog. No pending codes.

Setup 2: Berk HFC as is.
Result: CEL within 20 miles. CEL is P0136, with P0138 pending.

Setup 3: Berk, 1 defouler drilled out.
Result: CEL within 20 miles. CEL is P0136, with P0138 pending.

Setup 4: Berk, 2 defoulers, both drilled out.
Result: CEL within 20 miles. CEL is P0136, with P0138 pending.

Setup 5: Berk 2 defoulers, both drilled out. Steel wool between defoulers.
Result: CEL within 20 miles. CEL is P0136, with P0138 pending.

Setup 6: Berk, 3 defoulers, 1 drilled out, other unmodified.
Result: CEL within 20 miles. CEL is P0136, with P0138 pending.


I have reverted back to the OEM setup (setup 1) to verify 02 sensor functionality. Then retested... still popping CEL. It's my guess that the spacing isn't right, since the OEM setup is showing full readiness.

My only other guess is, for some reason, the defoulers are causing some electrical grounding issue.

P0136
P0138

 

I run a berks 70mm HFC on my 04 zero problems with the stock tube that they weld in. Could there be an exhaust leak at the header - cat meeting maybe it is scavenging air there. also with the test pipe any check engine lights?

 

I can't remember if the primary and secondary sensors are the same on the '04, but if they are, I would try swapping them. Otherwise, I would replace the secondary.

 

I too run a Berk 70mm HFC with no issues

 

bugger... was hoping someone had a magical combination. The sensor could be super super sensitive... but works perfectly fine with the OEM cat.

I'm getting to the point of just selling the Berk, getting a test pipe, running the defoulers, and calling it a day.

 

Im getting Berks HFC 70mm to add to my spoon Dual exhaust, Do I need to worry about the engine light coming on?
Its an 03AP1
I

 

I had my Berk HFC for 3 yrs before getting a CEL. One antifouler didn't work but two did. Try adding one more antifouler.

 

I was told with the Berk 70mm HFC i will get gains of 5whp and car will sound more mean.

Any thoughts on this fact?

 

The HFC may add a little since it's more free flowing but most of the sound will be a function of your muffler system. If your adding to an OEM, their probably will be only a little change if any.

 

have berk hfc 63.5mm with built in celfix, it never had CEL when on stock ecu
20k miles later on ems still no CEl