I have a CRX Si that has a DC 4-2-1 header that was installed by the previous owner. he place the O2 sensor back where the header comes to the one pipe. it's about 3'' maybe from where the header and the rest of the exhuast meet at. I'm wondering if the sensore is located in the wrong place, give the ECU a bad reading, and that is what is making my car smoke some and idle bad.


Modified by george34 at 8:15 PM 10/29/2005

 

are you thorwing any codes?

 

no codes. just some white smoke and i want to make sure it is my headgasket before i take my head off and find a good HG.

 

if the some is white its your head gasket..

 

most of the white smoke is gone now. it just will like pulse a little smoke out about every 5 secs. I think if my O2 sensor is in the wrong spot that my ECU would be getting a bad reading. which would not give my engine a constant amount of fuel.

does that sound reasonable.

Where is everyone putting there O2 sensor on an aftermarket header for an Si???

 

If the O2 sensor is back by the Cat, its right...the older DC's had the 02 sensor closer to the head.

I believe DC put it there because they new the exhaust would be a little cooler back there, so the 02 would read a leaner, then your ECU would give a little more fuel... thus richin up the fuel mixure a bit

and giving most guys a little more performance..

 

ok. i thought the guy i bought the car off of might have gotten the threads welded at the wrong place

 

should of just added this to your post about your head gasket https://honda-tech.com/zerothread?id=1414918... no reason to make two threads on this

But to the topic at hand about your head gasket. I think it is. I would change it if I were you. Better to know it was done right then just asume to was done right.