Hey, well I'm new to Honda-tech, but I love it already!

I have an automatic '97 accord, and I put in a K&N cold air intake, a 4-2-1 exhaust header, a hi-flow cat, and a hi-flow exhaust. But after we put in the new exhaust header and hi-flow cat, my check engine light has been on. I'm guessing its because of the two O2 sensors.

The top O2 sensor is mounted on just one of the four exhaust tubes, and the lower O2 sensor is mounted at the tail end of the exhaust header, just befor it conects to the new hi-flow cat. With the stock setup the lower O2 sensor is on the tail end of the catalytic converter, where it conects to the exhaust tubing. Is this where the problem is?!? And what are my options for fixing it?! (other than electical tape over the check engine light)

Please give me your input!

Thanks VERY much!!

 

If the 02 sensors are the same length down the exhaust as the original, it doesn't matter that it's only on 1 of the 4 tubes. Getting your O2 sensors all working great after putting on header/exhaust can be a pain. Try taking out the backup fuse for five minutes to let the ECU reset, then put the fuse back in, start the car, and let it idle for ten minutes to give the ECU some conditions to go off of. If you still have a check engine light, there's no easy way to get rid of it aside from going back to stock exhaust. The CEL might effect your gas mileage a little but that's it. When an O2 sensor code is thrown the ECU reverts back to a factory gas/fuel ratio instead of creating a dynamic one for optimum detonation/mileage based on the readings. Good luck.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Twixle &raquo;</TD></TR><TR><TD CLASS="quote"> Try taking out the backup fuse for five minutes to let the ECU reset, then put the fuse back in, start the car, and let it idle for ten minutes to give the ECU some conditions to go off of. </TD></TR></TABLE>

Forgive me, I'm not really familiar with the electrical side of the car. where is the backup fuse on the car? and is there anything else I should know when doing it?

Thanks very much!

 

Your 2nd O2 sensor is trying to measure the activity of the cat. So it HAS to be at the outlet of the cat, or it'll think the cat isn't working.

Plug that fitting, & have a new sensor bung installed in the cat where it belongs. Or if your 'high-flow cat' is really a test pipe, that won't work & you'll have to do something else.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">

Plug that fitting, & have a new sensor bung installed in the cat where it belongs. Or if your 'high-flow cat' is really a test pipe, that won't work & you'll have to do something else.
</TD></TR></TABLE>

Yeah that was my first thought, because the high flow cat is pretty much a glorified test pipe, there are the catalytic converting parts, but there is still a strait shot through the cat, so the readings are way different then stock.

Where is the back up fuse Twixle is talking about?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Twixle &raquo;</TD></TR><TR><TD CLASS="quote"> Try taking out the backup fuse for five minutes to let the ECU reset, then put the fuse back in, start the car, and let it idle for ten minutes to give the ECU some conditions to go off of. </TD></TR></TABLE>

Thanks!!

 

dont worry about the fuse, go to http://www.o2simulator.com/
and buy the universal single output o2 simulator. i did after getting a test pipe for my 99 and ive had no problems at all....

a wiring diagram will be your friend during this adventure

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Berry Pepper &raquo;</TD></TR><TR><TD CLASS="quote">Where is the back up fuse Twixle is talking about?
</TD></TR></TABLE>
I never owned a 5th-gen so I'm not sure. Disconnecting the battery works too, but you'll have to know your stereo's security code.