serious

here is my emissions test diagnostic report:



this is on a stock '90 civic dx hatch. what i noticed is that later in the test, and when my speed was up, the levels dropped to below acceptable. so....what do i do to pass?

if i moved things up and swapped in the d16z6 before i need to retest on the 27th, would that do it?

Katman

if you go D16Z6, the smog people might notice its a newer motor than your car and you'll have to be compliant with OBD1 type wiring and ECU. You'll basically have to convert your car to OBD1.

as for your DX motor, have you tried putting a new 02 sensor on? and how's the catalytic....old/new/don't know?

serious

i'm in maryland, so there's no inspection, only the emissions test. i've already converting it to odb1, so that's not a problem.

the got the car less than a year ago, so i don't know about the o2 sensor or the cat, but i haven't changed either.

Katman

ok, so you're running a 4-wire 02 sensor and an OBD1 ecu now? if so, which obd1 ecu are you running?

serious

right now i'm just running stock, with the 89 engine and unheated o2 sensor. would putting the engine in before the next test help me pass?

Crazydave

damn.. you're screwed all the way across....

have you checked operation of your o2 sensors..
put it on the scope.. and watch the flucuations..

or if your volt meter has a hold funcion..
has the max and min voltage?

mechanized

they stoped emissions years ago where i live but,what i used to do with my car was :if you have a race track close buy ,get some "100 oct." put that in your car and try to run your car real hard so your cats nice and extra hot right befor the test.

Crazydave

if you're o2 sensor is working..
then probably your cat..
all three of the gasses are high..
making me think the cat isn't working..

BigMoose

It looks like you were either running rich or the cat did not light off early on. I have an old beater chevy celebrity 14 years old and near 200K miles, a real POS. My wife just passed emissions testing by going right after I changed the oil (reduces some unwanted hydrocarbon infiltration from the crankcase) and running the snot out of the car on the interstate then taking it right to emissions testing. I had her keep it at a fast 1400 RPM idle untill it went on the rollers.

Older cars have trouble lighting off the cat if you have to shut it down and wait to get on the dyno.

Hope this helps some.
Regards,
BigMoose

Zatar69

Wow those are some bad scores!

Do you even have a catalytic converter? Check to make sure it's there and not hollowed out.
Also check your O2 sensor as it may be toast.

Are you running a chipped ecu by any chance?

Also- 100 octane gas may help but you may still fail HC's with that as it will contain more toluene.