AndyP

I just installed a test pipe with my HKS hyper and was wondering what others have done to avoid a check engine light.

What I did was I plugged the o2 sensor bung in the test pipe with an old o2 sensor with the wires snipped. My original secondary o2 sensor is tied to my tranny....but now the infamous "check engine" light is on. Is there any way to not get a "check engine" light from appearing??...other than covering up the display on the instrument panel?!

chungtaho0918

sorry dude, there is no way to get rid of that light......the ecu is too smart...I have the same problem, too....

Sideways

Someone on the board a few months back extended theirs outward a little bit and it worked. You should be able to find it by searching test pipes. Also, the Mugen ECU will let you run a test pipe.

OneQuickS2K

Running a $1000 Mugen ECU just to get rid of the secondary o2 sensor might be overkill. Here's a $40 solution. It has been proven and work on so many Honda OBD-2 ECUs. I have not seen any with it on S2000 yet but I hope it will work. Let us know how it works out for you. Here's the links:

http://jdmfan.com/technical/performance/o2...nsor_simulator/

http://www.casperselectronics.com/cgi-loca...product=IMPORTS

http://www.diabloautosports.com/product_in...roducts_id=2198

Basically, it's an O2 simulator which fools the stock ECU that
the O2 is reading the correct voltage. Same idea for a Check
valve or Comtpech ESM on a MAP sensor.

VTEC Racer

How much has the sound of the exhaust change with the test pipe? Any performance gains?

AndyP

The sound is amplified ten-fold with the test pipe on the HKS!! It already sounded good before, now it sounds amazing...like a 2 liter sportbike!

Also, IMO it cuts the boominess down greatly with the top up. Performance gains minimal on the top end....gotta get rid of the CEL.

Thanks OneQuickS2k. I'll try it and let you all know.

OneQuickS2K

I think running a straight pipe will help up top. You *might* lose a little low end due to no cat. (unless you're turbo'ed) but on the top end, you'll gain a few horses. We did the mod to my friend's Integra GS-R (B18C1 motor) and shave 0.1 off the 1/4 mile.

cbender

I tried the same approach -- zip tying the sensor to the tranny and using an old sensor to plug the hole. I got the same result. The CEL came on within three cycles. Having someone weld an extra bung onto the pipe in order to move the sensor out of the mainstream of the exhaust flow seems inconvenient. Has ANYONE tried the simulator? I've asked importparts.com and diabloautosports.com and neither knows if it'll work on an S2K. Any thoughts or suggestions? Thanks.

marcucci

You can also pull the BACKUP fuse from the under-dash fuse panel. You never complete more than one driving cycle, so the light never comes on.

AndyP

So aside from the light coming on, there are no lack of performance issues from the ECU?