Hey guys, Im lost.

I just transplanted a 2000 b18c from my 97 hatch to a 00 hatch. in the 97 everything ran fine. Now the idle is acting up and the car is super rich 12:1-13:1, I had to change the harness to a 2000 b16a2 harness and add a ecu adaptor to run the ITR ecu. But every thing else is the same so I dont know whats up, and no CEL.

 

that's not even that rich. 10:1 would be "rich"

 

At idle the car smell like rotten eggs. I would hate to get pop by a cop, saying my car is illegal.

 

ohh Cali, yaa emission's sucks, is it a B18C5? if not maybe the problem lies in having an ITR ecu on a motor with lower compression then it's tuned for?

 

I took the whole set up from a JDM ITR and transplanted it in to my 97 then the 00.

 

In the old set up the car would run 14ish and maybe hit low 13's when vtec would come on, so anything in the 12's is rich especial at idle. Hell my rotary idles in the low 14's.

 

Have you done any diagnosis?

 

No I haven't, I was thinking it had to be in the ecu harness adaptor or the wiring, since nothing else has changed.

 

14 is lean man, you wanna be 12.5-13.5 range.

 

Even so, why would the AFR change from car to car?

Really I moved almost everything from a perfectly running car.
I ran the car in the 14's for 8 years and 20,000 miles with no issues.

 

Rotten eggs sounds like a bad cat. converter

 

The small is common in cars that have high levels of sulfer in the fuel or running rich.

 

The AFR didnt change, something went bad. I would check out the coolant temp sensor and O2 sensor. Both of those can go bad without setting a CEL. I cant speak much about the harness differences though.

 

The egg smell usually comes from a bad cat or a blown open battery. My car runs pretty rich atm (untuned) and it doesnt smell like that at all. Where is your wideband sensor located? Please tell me if you have a cat that its before the cat..
What is different about the 2000 harness? Did you have to wire anything differently? Because if so then that could be where the problem lies. Does the car run badly or blow black smoke?

 

well the 96-98 civic and 96-01 ITR all have OBD2a harness, and the 99-00 civic have OBD2b harness. So I used a 99-00 si harness, all I had to do was lengthen the wire on the IAT.

I do not have the 2nd o2 sensor, and only one cat. the Wideband is located inline after the collector infront of the cat.

 

Well not a bad idea, I'll take a look at the O2 sensor, since the car has started backfireng. Im pretty sure the CTS is good.

 

How are you sure the CTS is good? What happens is it tells the ECU its colder than it actually is and the ECU responds by enriching the mixture. With no CEL I don't think the harness has anything to do with it.

I would test the CTS first as it is easier. You want to make sure everything else is running ok before you condemn the O2 sensor.

Just wondering but are you OBD2? If you are sensor testing should be cake. You can just check sensor values with the scan tool.

 

Well the fans are coming on and the dash is reading normal.

 

That has nothing to do with it. There are 2 temp sensors and a temp switch. The switch is for the fan, there is 1 sensor for the gauge and 1 for the ECU.

The one for the ECU is the one I am talking about.

 

Really? where is that one located? The Engine is a JDM ITR.

 

thye are typically both located on the side of the head under the dizzy. One is 1 wire (gauge) the other is 2 wire (ECT) and then there is another one in the housing that is used to turn the fan on and off.