California Smog/Emissions Test Failure, High HC

[Prime]

I'm in California, so you guys here will know the drill. I'm a test-only bitch of the state, and so I'm kind of limited in my options here. As I'm also limited in funds for sending it to a Test and Repair shop, I thought I'd come here first.


Here's the gist: 1990 Nissan 240sx, swapped SOHC for a 91' KA24DE. Roughly 200k miles on the clock (didn't write down from donor car).

What I have, asterisk (*) indicates new since failure
New Catalytic Converter
*New Spark Plugs (NGK Platinum, properly gapped)
*New Plug Wires (Bosch, I know, I know...)
New Rotor and Cap
*New Injector O-Rings (Nissan OEM, not 3rd party)
Injectors all test within spec
Compression 149 +/- 2 across the board
Not burning any oil that I can detect
Timing set 15 degrees BTDC as I heard that helps with HC.

I was told I had a slight misfire at idle, which is why I've changed the above components. Now, for the numbers

@idle (650 per fsm)
%CO2 14.9 (Pass)
%02 0.2 (Pass)
HC PPM 169 / MAX=120 (FAIL)
%CO .11 / MAX=1.0 (Pass)

@2500~RPM
%CO2 14.7 (Pass)
%02 0.3 (Pass)
HC PPM 72 / MAX=140 (Pass)
%CO .37 / MAX=1.0 (Pass)

So... any ideas?

[Thursday]

cat msglngth

[Prime]

Originally Posted by Thursday

cat msglngth

Cat is new, like I said. I -really- doubt it would be the cat. Thing doesn't even have an oil change on it.

[drftem]

whats your idle set at and what is your timing set at at idle?

[Prime]

Originally Posted by drftem

whats your idle set at and what is your timing set at at idle?

Idle as 650 as it says above, editing to show timing @ 15 degrees BTDC,
and drove it 20 miles in 4th gear to get to the test site, cat was smoking hot.

[drftem]

and did you heat up the cat alot before taking it there?

[zylvia213]

Check the timing. Some of these smog guys mess w/ the timing to get the car to pass. PM prime i can help you out with this.

[Oo_Skyline_oO]

check your egr valves and vacum hoses, those are very tempermental, if those are bad, very good chance you wont pass.

[reccakun08]

go to advance autoparts to get guarenteed to pass emission formula. worked for me.

[Prime]

Originally Posted by zylvia213

Check the timing. Some of these smog guys mess w/ the timing to get the car to pass. PM prime i can help you out with this.

Will do.

Originally Posted by Oo_Skyline_oO

check your egr valves and vacum hoses, those are very tempermental, if those are bad, very good chance you wont pass.

Alright, I'll give a look. I just replaced those last year when I swapped the motor over, but no harm in checking.

Originally Posted by reccakun08

go to advance autoparts to get guarenteed to pass emission formula. worked for me.

I've seen that stuff, but always felt kind of wary about it... I've got the time, so I guess it couldn't hurt. I'll think about it.

[idlafie]

Check out my response from a previous thread.....

http://www.zilvia.net/f/showthread.p...highlight=smog

Put your ECU into Diagnostic Mode & check for any trouble codes. Make sure your Engine Coolant Temperature sensor is working along with your Oxygen sensor. Also check the small vacuum line under the BPT valve. It's "L" shaped and usually cracks causing a loss of vacuum to the EGR valve.

Hope it helps...

ID

EDIT:
Damn CARB!!!...they went & changed the link on me!!!....this is the CORRECT CARB link....
http://www.bar.ca.gov/80_BARResource..._Glossary.html

[Prime]

Originally Posted by idlafie

Check out my response from a previous thread.....

http://www.zilvia.net/f/showthread.p...highlight=smog

Put your ECU into Diagnostic Mode & check for any trouble codes. Make sure your Engine Coolant Temperature sensor is working along with your Oxygen sensor. Also check the small vacuum line under the BPT valve. It's "L" shaped and usually cracks causing a loss of vacuum to the EGR valve.

Hope it helps...

ID

EDIT:
Damn CARB!!!...they went & changed the link on me!!!....this is the CORRECT CARB link....
http://www.bar.ca.gov/80_BARResource..._Glossary.html

Code 55, all clear. Did that earlier today. That specific vacuum line was cracked a month or two ago, I replaced it. Will check again. 02 and CTS are both under 3 months old and tested good when installed, but again, I can check. Haven't looked at your links yet, will do in the morning when I get up for work.

Thanks again, to everyone really.

[techn9ne]

for an easy fix, create a small, not very noticeable vacuum leak. since you are not in an enhanced area, you dont need a dyno test, and NOx is not measured. just make sure its hard to find.

[Prime]

Originally Posted by techn9ne

for an easy fix, create a small, not very noticeable vacuum leak. since you are not in an enhanced area, you dont need a dyno test, and NOx is not measured. just make sure its hard to find.

Assuming extra air in the intake mixture, kills HC? Hm... could just get a T fitting, leave one end open at the back of the motor maybe... Good idea, lemme do some tinkering...

Originally Posted by DohcKA

use a bottle of sky blue

Sky blue? Never heard of it. I've done the Seafoam thing before, but this is new to me.

[DohcKA]

use a bottle of sky blue

[xsparc]

sky blue... as in vodka?

[SexPanda]

Oh yeah, full your take up like, 3/4 the way, then pour in some everclear...

Seriously, get some uh...

Seafoam. Thats it. couldnt think of the name. It'll clean up your engine real good like, tell you what boy.

[handinpants]

how much money are you going to have laying around to pass this smog?

[Lucient]

Use a quart of denatured alcohol. Search around the net. This stuff works. My car failed the sniffer horribly and with the alcohol I passed with flying colors with no cat. I repeat with no cat. I have several friends that have passed with their SR and RB powered cars with no cat. Just run you fuel down to 1/4 tank and pour the alcohol in run it hard for a few miles and go get it tested