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Grrrr, Failed Smog after turbo swap! Help!

  • Thread starter Thread starter KenneBell
  • Start date Start date Mar 22, 2006

KenneBell

New Member
Apr 14, 2005
158
0
0
San Jose California
Mar 22, 2006
#1
  • Mar 22, 2006
  • #1
Grrrr, Failed Smog! Help Please!

Put the 88 Turbo coupe motor into my 92 stang. I put on a new cat. The guy I went to is pretty cool, he said he would disregard whatever was under the hood if I passed the sniffer. Well Shiitte, I passed everything except NOx. What causes that? Anyone fail before because of NOx, what did they change to pass? Thanks!!
 
B

BELL

Founding Member
Feb 21, 2002
722
0
0
California
Mar 22, 2006
#2
  • Mar 22, 2006
  • #2
how bad did it miss? i'd start with a good tune up with motorcraft parts, plugs, dist cap and rotor. Check the timming and egr valve. CA smog in the bay area sucks. mine failed the other day on HC's (cat is probably shot)...
 

Dan P.

Founding Member
Apr 26, 2002
483
0
27
N.C.
Mar 22, 2006
#3
  • Mar 22, 2006
  • #3
might want to get the cat good and hot before you have it tested next time
 
B

BELL

Founding Member
Feb 21, 2002
722
0
0
California
Mar 22, 2006
#4
  • Mar 22, 2006
  • #4
hmmm good and hot means i can go really fast...right...
 

KenneBell

New Member
Apr 14, 2005
158
0
0
San Jose California
Mar 23, 2006
#5
  • Mar 23, 2006
  • #5
Good and Hot, just how I like my women, lol! I think it is the EGR, the the EGR has a restrictor if I remember right. It narrows the egr inlet to about 1/8 inch hole at the back of the manifold. I figure this hole is plugged with carbon and maybe if I clean that out it will do the trick. Already have complete tune up done.
 

Brantley

Founding Member
Feb 29, 2000
1,329
0
0
Memphis, TN
Mar 25, 2006
#6
  • Mar 25, 2006
  • #6
NOX is a byproduct of high cylinder temperatures... make sure your EGR is working.. I know y'all know what EGR does, HOW it reduces NOX is by effectively reducing the cylinder's displacement with unburnable exhaust air.. there is no/very little oxygen left in the exhaust after combustion, so it won't reburn. Less burnable mixture = cooler temps = lower NOX. So... I'd just make sure the whole EGR system is in good working order with no restrictions, and I would think you should be ok.
 

towbar

Member
Dec 19, 2004
21
10
14
Akron, OH
Mar 25, 2006
#7
  • Mar 25, 2006
  • #7
I dont know what the min standards are in Ca, but here i passed without the egr even hooked up. It is on the car but only the exhaust pipe is connected. Not saying that this is not the problem. The first time i took it the car failed big time. I didnt check the timing before I went, but somehow my timing got to around 15*. I adjusted the timing back down to 10* and took it back and the car passed with ease. Too much timing will cause combustion temps to go up creating more NOX.

Just from my experience.
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
38
119
Antelope Valley, SoCal
Mar 25, 2006
#8
  • Mar 25, 2006
  • #8
I can't really add anything to the EGR recommedation.

The emissions limits for this wonderful state are:

15mph: HC 138ppm, CO 0.85%, NO 1148ppm
25mph: HC 113ppm, CO 0.65%, NO 978ppm

The only part mine was borderline on was HC. Mine just squeeked by at 138ppm.
 

KenneBell

New Member
Apr 14, 2005
158
0
0
San Jose California
Mar 25, 2006
#9
  • Mar 25, 2006
  • #9
I PASSED!! WOOHOOO! I cleaned the egr and disconnected the spout so the timing stayed at 10 degrees, disconnected the FPR so it would run rich and cool the cylinders, and passed with flying colors! Thanks for everyone's help.
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
38
119
Antelope Valley, SoCal
Mar 25, 2006
#10
  • Mar 25, 2006
  • #10
Really? What were the measurments?
 

KenneBell

New Member
Apr 14, 2005
158
0
0
San Jose California
Mar 25, 2006
#11
  • Mar 25, 2006
  • #11
15mph C02=15.2 02=0.1 HC=14 CO=0.01 NO=240

25mph C02=15.2 02=0.0 HC=62 CO=0.05 NO=81
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
38
119
Antelope Valley, SoCal
Mar 26, 2006
#12
  • Mar 26, 2006
  • #12
Damn, thats a clean car!
 
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