to make a long story short, i have a 00 civic si b16a2, i put aftermrkt cold air headers high flow cat, cat back exst plugs, wires msd cap with exteral coil. check engine light has been on since header went on, went to honda dealership(never do that again !! to get 70k valve ajustment,it was running fine up till then other then the light which i was told by the same dealership was a oxygen#2 sensor with low voltage and somthing about short term fuel trim,. but now 5 min after start, when i stop at red light idel drops so low it almost stalls, and the check engine light flashes as well, no one will touch it. please help, any comments might help, big ups to honda-tech !!

 

telling us what CEl is flashing will help us help you.

 

Hey,

I've got a '01 EX D17a2 VTEC with just about the exact same mods (DC headers, cold air intake, removed cat, replaced with resonator, cat back exhaust, among many other things) and i have the exact same problem. My check engine light stays on all the time, and everytime i stop, my rpm's kick down to about 100, almost dies, then kicks up to about 600 and idles really rough. If i reset the ECU, the light stays off for about 500 km's, then kicks on again. And when the engine is cold, it searches for an idle like crazy, but cant find one. And same thing, no one can tell me what the deal is, not even honda. Honda originally told me the cat was clogged, so i had it cut off and installed a resonator pipe. But no luck at all. Any help wiould be great. (by the way, cleaning or replacing the IACV vavle doesnt work)
Thanks

 

from my experience with o2 sensors , with a volt meter check the 1st o2s and u should see the voltage jump .15v to .85v if it does then sensor is working. check the 2nd one and should see .45v a straight line on oscilliscope if the cat is working properly. low voltage DTC's on 2nd sensor usually means lean cat or not working cat i should say. i have your mods too and it works fine.

use PGM-tester to adjust rpm in newer model vehical


Modified by Dyn0speed at 9:42 PM 6/25/2004

 

you guys might want to ask in the rsx or eg forum. this is 4th gen civics.

 

hey

Can anyone tell me how to tune my idle RPM's up on a 2001 civic EX with a D17a2 engine? Apparently, there is no screw on the throttle body, and I've been told that the only way to do it is through the ECU with a diagnostic computer. Is this true?

Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mr. carpenter &raquo;</TD></TR><TR><TD CLASS="quote">you guys might want to ask in the rsx or eg forum. this is 4th gen civics.</TD></TR></TABLE>

This is the EF forum, but from my experience with stock o2 sensors, almost any time i swap out an old header and mess the the stock o2 sensor, it dies and you need a new one. I just plan on it now ahead of time. On obd0 systems though a dead o2 doesnt really change drivability THAT much. However with obd2 systems it is likely to be much more sensitive to change. I would suggest getting new o2 sensors, at least test them like suggested above.

 

1 o2 should be AFTER the cat.. thats more likely the problem.

 

o2 sensor, but this is for EF 88-91 civics, check the EG+ forums....