So I have an 89 CRX with a d16z6 in it it won't pass emissions because of Co I put a catalytic converter and o2 sensor 4 wire and change the the tuned ECU that I have in it for a stock one no check engine light with the tuned ECU but with the stock ECU the check engine comes on and still doesn't pass emissions don't know what to do any help would be greatly appreciated

 

I have a 1991 Civic Wagon RT4WD. When I bought it a few months ago, it failed California emissions. All the emissions were very high. So I changed the spark plugs, air filter, and used CRC Guaranteed to Pass. Then took it back for testing, and it passed with flying colors...all the emissions were very very low, well under the maximum limit.

 

<p>You get a check engine light so obviously you won't pass. &nbsp;even if you happened to pass the sniffer test, I think they can fail you simply&nbsp;because of the check engine light.</p><p>did you pull the codes to give an idea for the the problem is?</p>

 

Correct. My friend passed the sniffer (barely) but the guy said he failed because he had a CEL. Can't remember off the top of my head what CEL it was, this was about 8 years ago.

OP, pull your codes and fix them. Also, if your car is a dx or hf, chances are it might not pass with a z6. My std couldn't pass with an a6 mpfi swap, even with all new smog equipment and running in tip-top shape.

 

The DX and HF are no less likely to pass with engine swaps than an SI.