Rep Power: 0

hey i just installed a fuel/ratio guage in my 03 EX and now my check engine light is on, any ideas?

 
Rep Power: 812

the a/f ratio gauge alters the voltage reading and sends the wrong signal to the ecu. get rid of it or your O2 sensor will get ruined, if it isn't already. And get the code checked to see what it is. I bet something with the sensor.

 
Rep Power: 309

My check engine light came on but that was when I put Header and cat-back, I assume it does not affect performance, right?

 
Rep Power: 812

a broken 02 sensor will severely affect performance. thats how the ecu determines the air/fuel calculation.did you take off the cat? a header and exhaust normally should not cause a check engine light unless you have a leak somewhere.

 
Rep Power: 309

The thing is that I installed the HP Racing header and that crap was the one that forced the engine light to come up I think, then I installed the Kamikaze header and still the light is on.

 
Rep Power: 812

thats only if he doesn't have a secondary 02 sensor. just pull the battery cable and the light will go off.

 
Rep Power: 309

but I have not noted a loss in performance, my civic is very responsive and the mods increased greatly its top end and low end and I can own my cousin's tiburon every day, its the 4 cylinder, but I'm concerned because of the Check engine light.

 
Rep Power: 309

I have a downpipe, so no cat...and i've tried to plug out the battery cable and the light comes on in about 20 minutes.

 
Rep Power: 812

okay if you don't have a cat, you need some kind of 02 sim or mil eliminator to make the ecu think you have a cat. but no it won't affect performance but the engine light will always be on (not good because if some other real problem happens, you won't know)./

 
Rep Power: 309

Ok, thanks gearbox, where can I get good O2 simulator? Is there a simulator that cheats a sensor that there is always cold air running through the intake? Cause I have the V2 but it gets heat from the motor. Thanks!

 
Rep Power: 309

Thanks, how's the install?

 
Rep Power: 453

When a check engine light is on, the ECU has detected a fault in the vehicle. Whether it be a bad signal givin by a sensor, a vacuum leak, leak in the EVAP system, faulty cat converter, anything. Depending on the problem, depends on what the vehicle will do. alot of times a car will have a check engine light on and will still run fine. No decrease in fuel mileage. most of the times its something simple. Other times the car will run like ****. when you have a faulty TPS sensor, that will effect how your tranny shifts, and your driveability. One failed component can effect 10 others. The ECU isnt going to add fuel when the check engine light is on. It may if it detects a 02 sensor reading too lean. But more then anything, it justs lets the driver know there is a problem.

Now The 02 sensors monitor the 02 content in the exhaust. the primary 02 sensor detects the oxygen coming out of the engine and if it detects a rich oxygen content, it will signal the ECU to lean out the mixture. If it detects a lean oxygen content, it will signal the ECU to richen up the mixture. they are used to adjust the air/fuel mixture. the secondary 02 sensor monitors the cat converter and make sure it is doing its job. if that second o2 sensor senses the same oxygen content as whats coming out of the engine, then it will signal the ECU that the cat isnt doing its job.

 
Rep Power: 0

Got my mil eliminator at bigjoshracing.com but that site no longer exist. But found one on ebay.

http://cgi.ebay.com/ebaymotors/MIL-e...spagenameZWDVW

 
Rep Power: 257

i dont know if this has been answered earlier, i just dont feel like reading each reply, but as far as i know, ( i have an LX) the LX if u replace ur old manifold with a header, the "check engine" light will go on, simply because, i dont know if u noticed but on the stock manifold, it kinda looks like it has a cat, right their on the manifold, and right above is the sensor, yet on a aftermarket header, its just more air going through, which does not have a cat, so the sensor reads different air pressures as it used to, so thats why it comes out, well atleast thats what i was told

 
Rep Power: 309

thanks!

 
Rep Power: 309

I found this one, seems a lot easier for me, what you think?
http://cgi.ebay.com/ebaymotors/Honda...QQcmdZViewItem

 
Rep Power: 453

yes the LX models have the cat converter in the exhaust manifold, so replacing it with a header will throw a code. the sensor isnt reading different air pressures, it is reading the exhaust content coming out of the cat. and signals the ECU as to whats going on. if the cat isnt there, there will be a different signal sent to the ECU and the ECU will reconize there is a problem and turn on the light.

 
Rep Power: 257

does that make u lose hp?

 
Rep Power: 309

Can you tell me the brand name of your simulator?

 
Rep Power: 309

My problems are gone, my buddy HiVtec sole me his 02 casper simulator and no more check engine light for me

 
Rep Power: 0

is it possible that the check engine light could come on just reminding you to change oil every so many miles??

 
Rep Power: 812

no. thats the maint reqd light.

 
Rep Power: 0

wth I ask for help in this forum and i slaped across the face....

 
Rep Power: 812

but i just answered your question...

 
Rep Power: 0

The maint req light is a signal telling you to do scheduled maint like changing your oil; however, it's not going to come on everytime you should change your oil. It comes on at the 10k mark and so on. They (honda dealerships) want you to check all the hoses and crap. Check your manual for the correct mileage. You can turn it off by unplugging the battery.
hope that helps.