I took my 95 cx hatch to go and get my emissions for the second time and failed. i have a D16y6 with a P05. Only mod is a short ram intake.

Here are the numbers for the first failure

15 MPH
Limit Reading Result
183 177 failed HC PPM
.73 .30 Pass CO%
2400 2365 pass NO PPM

25 MPH
Limit Reading Result
200 333 Failed HC PPM
1.07 5.98 Failed CO%
2333 605 Pass NO PPM

After that they said it was a bad cat, so a friend had a cat, so i put that one on.
Here are the numbers for the second failure.

15 MPH
Limit Reading Result
183 195 Fail HC PPM
.73 .37 pass CO%
2400 1141 pass NO PPM

25 MPH
Limit Reading Result
200 392 Fail HC PPM
1.07 5.77 Fail CO%
2333 572 pass NO PPM

I need help. does anyone know if anything else is the cause of this?

 

O2 sensor.

Cat's and O2 sensor's are the normal causes of failure.

Please tell me that you did a tune-up too.

What happens is the O2 sensor starts to go by either slow movement or sticks at a certain voltage. Once this happens the cat gets burned up because your air/fuel mixture is haywire.

Did you look at the cat you took off? Was it hollow? It might not have been bad.

 

I did the tune up but never thought about looking through the cat to see if it was hollow, as i am new to all of this stuff. so if i change the o2 sensor it should fix this?

 

No man you need to listen you prob need a new cat and o2sensor, the sensors arnt that much, but the cat is where you run into the cost problems. I believe your car is OBD1 so you have to find a cat that will fit. I have heard of people paaing with the $60 universal magnaflow cats, but dont hold me to that. Hope this helps

 

hey man make sure you drive your car for about 20mins, buy a cat and 02 sensor brand new, and if you can before you actually take it to smog water down the radiator with water

 

You guy's..... he said he had done the cat before the 2nd test.
EDIT: alright it was a used cat not new. My bad!

Yes the O2 sensor should fix you right up.

EDIT: Also run the car for a day after you do the cat. New, or ones that have been sitting are not as efficient. You need to burn them in for an hour or so of driving.

 

replaced my o2 sensor and left my cat alone and passed my emissions. thanks smogman and everyone else.