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I NEED EMISSIONS HELP WITH MY 93 5.0 PLEASE!!!!!!!!!!

  • Thread starter Thread starter TurbomanTSi
  • Start date Start date Mar 18, 2004
T

TurbomanTSi

New Member
Nov 12, 2003
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Mar 18, 2004
#1
  • Mar 18, 2004
  • #1
I have a 93 5.0 with 90k miles on it. It has two cats and I put new plugs and a new smog pump into it. I have a MSD 6AL box with a BBK cold air. I have a full exhaust with full length headers and a superchip. I keep failing on hydrocarbs pretty bad. I have failed 6 times and I dont know what to do! Please help me out if u can. email me if possible at Kmnsk6@aol.com
 
A

Akshay

New Member
Mar 15, 2004
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Mar 18, 2004
#2
  • Mar 18, 2004
  • #2
Remove the superchip, check timing (probably too advanced because of chip), clean/replace egr (if vacuum is present), and replace pvc valve. Check for any vacuum leaks too.

Akshay
 

91five-o

New Member
Nov 16, 2002
287
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Maple Ridge British Columbia
Mar 18, 2004
#3
  • Mar 18, 2004
  • #3
My car failed four times, each time I kept taking more timing out of itand the idle test kept getting better but couldn't get the reading low enough. My car was failing on the idle test only with hydrocarbons. The driving test passed with flying colors the first time through and actually kept getting better everytime i took more timing out of it. Anyway, the last time I failed, my timing was set at 2 degrees and that's when I gave up and took it to a shop. I was close but didn't want to keep wasting money. Long story short - the shop dropped the timing to 1 degree, idle at 1050 rpm and it passed. Hope this helps.

Rick
 

donkey_punch

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Jan 16, 2004
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northern****ingjersey
Mar 18, 2004
#4
  • Mar 18, 2004
  • #4
also change your O2 sensors, my want to look into new wires, and run some good gas
 

jrichker

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Mar 10, 2000
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Mar 18, 2004
#5
  • Mar 18, 2004
  • #5
If you have an adjustable FPR, drop the pressure down to 34 PSI or less.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
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Charlotte, NC
Mar 18, 2004
#6
  • Mar 18, 2004
  • #6
Guys is it possible this has anything to do with his longtubes and the O2 sensors being located too far away from the stock location? The LT's usually place the O2's a foot or two further back in the system. With more time for hydrocarbons to oxidize in the stream before reaching the O2's, they're seeing a leaner signal, and consequently the computer is injecting a bit more fuel than it should resulting in the higher HC reading. Just a shot in the dark.
 
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noslow5_0

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Nov 7, 2003
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dallas tx.
Mar 18, 2004
#7
  • Mar 18, 2004
  • #7
Michael Yount said:
Guys is it possible this has anything to do with his longtubes and the O2 sensors being located too far away from the stock location? The LT's usually place the O2's a foot or two further back in the system. With more time for hydrocarbons to oxidize in the stream before reaching the O2's, they're seeing a leaner signal, and consequently the computer is injecting a bit more fuel than it should resulting in the higher HC reading. Just a shot in the dark.
Click to expand...

i could very well see that happening.... if all else fails, go gett a bottle of the rxp stuff.... suppose to make your car pass emissions.... it took quite a few points off of the hc and nox on a little crx that i had....
 
S

sleeper89

New Member
Nov 18, 2002
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Toronto, Ontario
Mar 18, 2004
#8
  • Mar 18, 2004
  • #8
two things come to mind:

1) IF you removed two cats: i don't remember which two do which, but one pair is for NOx and the others are for Hc and CO. this could be the prob. otherwise if you have an aftermarket pipe, disregard this.

2) what are your plugs gapped at? my first time through the sniffer i failed the Hc at idle. i was running ~.065-.069 (going from memory) with my jacobs. after i closed them down to ~.059 and had the re-test there were no issues.
 

Dardy

Founding Member
Nov 4, 2002
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Delaware
Mar 18, 2004
#9
  • Mar 18, 2004
  • #9
I use to go to autozone and get a bottle of g2p and i would pass emissions easily with no smog pump hell the only emissions on my car were cats i would reccomend it 100%
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Mar 18, 2004
#10
  • Mar 18, 2004
  • #10
Sleeper makes a great point - if you replaced dual cats with a single, it needs to be a 3-way cat - taking care of HC, NOx and CO.

Sleeper - would love to have details of which unit you have, and your impressions of your Jacobs ignition system. You can email me direct at myount@senndelaney.com or pm me. Thanks in advance.
 
T

tom2001gt

Founding Member
May 20, 2002
292
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Delran N.J.
Mar 18, 2004
#11
  • Mar 18, 2004
  • #11
My car passed emmisions with 150,000 miles on it no cats no smog pump long tube headers. I got the garenteed to pass emmisions stuff and set my timming to 0 and it went right through the car had no power with 0 degree timing but it passed.
Tom
 

stang&2Birds

Founding Member
May 4, 2000
2,091
5
58
New England. :-) CT/MA
Mar 19, 2004
#12
  • Mar 19, 2004
  • #12
Junk the car. Or, MORE INFO! It could be a ton of things. Without more info, you WILL end up junking the whole exhaust setup.

You need NEW O2 sensors, you need 3 way cats, you need the cats and o2 sensors to be hot enough, you must go into closed loop. Or, you need a good working EGR system. You need to have your timing right. And so on and so on. So, you can junk the car. Or, list (in a nice way) every thing about the test, the results, the standard, your car, the setup, etc.

Still, my guess is that there is very little chance you'll pass, in anyway, with your setup. Non coated long tubes are horrible for smog. They let out too much heat. The cats are too far down. Etc.

The superchip _should_ effect only WOT conditions. Unless, you have a custom *non smog legal* tune.

In short, you may have to put on the stock headers and h-pipe to pass. YOUR engine and the way it's tested in NOT the same as "joe blow" that passed with a million mods. Also, you'll NEED the smog pump working.

Can a stang pass with long tubes and no cats? Well, some people have. IMHO, they should have bought a lottery ticket with that type of luck.

BTW: Some states are now checking for the *number* of cats. More and more are. So, keep that in mind. A state can change smog testing procedures *anytime* they feel like it. An aftermarket h-x pipe is NOT smog legal. Never has been, never will be. But, it MAY pass SOME smog tests.

BTW#2: *I* did not make the laws, or create the laws of physics. So, don't complain to me. *I*, and many other, have to deal with the same thing.
 
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