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cyuenchon
12-12-2011, 05:29 AM
Bought and installed. Bought spacers and installed. Got one code: P0300- random/multiple cylinder misfire. Figured out problem, and fixed it.

Ive followed the thread on club4g, apparently they have received codes for misfire and multiple sensor issues. No one seemed to know why they were getting codes, or how to fix them without trying multiple times.

The OBX headers come with three O2 bungs toward the top of the manifold. If you plan on buying this header, youll need (and my great recommendation) to cap the O2 bung on the 4th runner (counting from Left to Right), and weld in two O2 bungs towards the bottom of the manifold. One on the 1st runner and another on the 3rd runner. For the bottom two O2 sensors you'll want to use spacers from http://www.o2-simulators.com/?gclid=CMzh9ajA46wCFUvCtgodhk5KpA , my reason for using these sims were originally based on cost...but after installing them, I havent received any codes from those sensors. On club4g they were using spacers that either didnt work or had to be modified to work.

Now for the reason we were getting the P0300 code. When installing, we're not paying attention to where we are putting the O2 sensors. Our top left sensor (bank 1 sensor 1) regulates cylinders 1 and 4 (counting from Left to Right). Our top right sensor (bank 2 sensor 1) regulates cylinders 2 and 3. Common mistake is that we attach our top right sensor into runner 4, which is normally taken care of by our top left sensor. That simple mistake leads to cylinders 2 and 3 to go unregulated and results in misfires. If this all really confuses you.....pay ATTENTION to your stock manifold, and see which O2 sensor each runner goes to.

If this helps only 1 person, Ill be satisfied.

Rach3T8G
12-12-2011, 06:29 AM
Good info

galant1983
12-12-2011, 07:39 AM
sweet info!!!

Gotti
12-13-2011, 10:28 PM
Do u have a picture install from front to back?

midiser
12-13-2011, 10:57 PM
thanks for the info.. have you felt the power gain after you installed them?

cyuenchon
12-14-2011, 10:47 AM
The current setup I have is a cluster f*ck, thats why I recommend the O2 placement that I do. Until I can clean up that mess, I may not post a photo......ehhh but I just might post one njust to show the head ache.

As for power, I cant immediately notice anything. The stock 4cyl manifold, in my opinion was an efficient design. Another reason why I may not feel anything is because my stock manifold was pretty damaged, as were the pre-cats. As far as sound goes, the rest of the exhaust system is stock. Even then I probly wouldnt notice since all I can hear is the suction of the CIA and the whistle of the GT throttle body.