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Help Passing smog test; Cali

  • Thread starter Thread starter 287ridah
  • Start date Start date Nov 9, 2004

287ridah

New Member
Jul 1, 2004
6
0
0
Nov 9, 2004
#1
  • Nov 9, 2004
  • #1
I got a '89 5.0 auto that failed HC & NOx. The NOx might be from not turning on the fan and the combustion chamber running to hot +2500F!!
I bought the car from a tow yard and haven't found out all the mods the guy before me did. My timing was advanced when I went in (around 12degree's) and I didn't drive far to the smog spot so my catalytic converter was probably not hot enough. I retarded my timming to 8 degrees and plan to run her on the freeway and get the cat red hot before going again. + Im turning on the fan Any other ideas on helping her pass.
Does putting one of those fuel additives or something in the tank help when passing smog tests.
Oh yeah, Im in California!!
Or if anyone knows of any old posts that I couldn't find..let me know.

Also, the timming marks below the pulley doesn't read correctly. When I did my timming it read 0 , 1, 2 ,3 with marks between each number.
I guess 1 was like 10 because below that the engine would die and above it the engine would advance. does anyone else seem to show this???? I think its fine since the engine is running fine but I just wanted to ask.

Thanks for any and all help
 

At1Maverick69

Member
Aug 21, 2004
220
0
16
San Leandro, Cali
Nov 9, 2004
#2
  • Nov 9, 2004
  • #2
hc is hydrocarbon ( unburned fuel), so it may be an ignition misfire of some sort, check ur plugs, wires. or have you replaced ur fuel filter? i think that'll cause it to go up too. NOx is caused by high combustion temp, check ur egr if it is functioning properly, converters, timing too. i hope this kinda helps
 

cdog301

Founding Member
Aug 30, 2000
236
1
18
richmond ,ca
Nov 9, 2004
#3
  • Nov 9, 2004
  • #3
smog

Sounds like it is rich you may want to change the O2 sensors and the base timing is 10degrees BTDC. hope this helps! Oh and I always use the guarantee to pass smog in a bottle stuff works evey time!
 

krahkin

Member
May 7, 2004
183
0
16
Acworth GA
Nov 9, 2004
#4
  • Nov 9, 2004
  • #4
You can mix methanol with gasoline and pass so so clean
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 9, 2004
#5
  • Nov 9, 2004
  • #5
Pull the diagnostic codes and be certain all the emissions systems are functioning properly. Does the car have an air pump and cats on it?
 

crazypete

All my crevices are greased.
Oct 22, 2004
930
4
18
Arlington, MA
Nov 9, 2004
#6
  • Nov 9, 2004
  • #6
Everything these guys said and

1. Change cap, wires, rotor, plugs. This is the first thing you do with any new car.
2. Verfiy existence of cats and smogpump
3. Pull codes to see if anything is malfunctioning.

If you are still having problems, you can goose it. Depends on how much they check.
For the test
1. Disconnect the check engine lightbulb
2. Run the smogpump tube directly to crossover behind the heads.
3. Run a hose from the h-pipe/4cat air injection tube in a sneaky fasion and dump it to the fender.
You are now adding more air earlier and dumping some exhaust.
4. Do the same with the hose on the side of the filler neck. Crankcase vapors are now being dumped.

If this still fails, get an alternator pulley and attach it to the smogpump front. You will need to drill 3 holes in the inner crevase of the pulley to get it to attach. DONT DRIVE LIKE THIS! Attach the pulley around the corner from the shop and dont idle there while waiting. The airpump _will_ sieze after 15 minutes of this but until then, it will be a supercharger for your exhuast. There will be practically fresh air bellowing out of your tailpipes.

I pass the sniffer in mass with a carb like this. No way you will fail with all that unless they find your sneakytubes and fail you for that.

Good luck
 

jrichker

StangNet's favorite TOOL
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Mar 10, 2000
27,512
2,811
234
Dublin GA
Nov 9, 2004
#7
  • Nov 9, 2004
  • #7
Dump the codes and see what the computer says is wrong…

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart.
 

287ridah

New Member
Jul 1, 2004
6
0
0
Nov 9, 2004
#8
  • Nov 9, 2004
  • #8
Wow thanks for all the replys!!

How do you view the codes?? I have several mustang books but they dont show how to view codes or I just missed them, (being impatient). One book said I need a device that cost big bucks!

jrichker: Do I need a hand scanner or is there a pulse light visible on the dash or something?? I must have missed something on those links.


The car has a smog pump but how can I check the cats without pulling down the system?? Can I put something down the pipe to check. Im not sure if the guy before me hollowed them out. Im probably gonna have to bring it down otherwise...

I did a basic maintenance to the car, wires, plugs, cap, rotor, etc. but will check again to make sure all is working. And I'll change the 02 sensor or atleast check it.

I changed down the timming to around 10 but those marks on it seem funny. It didn't show 8, 9, 10, 11 etc like my other cars but showed 0, dash, dash, dash, 1, dash, dash, dash, 2, etc...

Again thanks alot for all the quick advice. I'll reply again and let ya'll know how she did.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 9, 2004
#9
  • Nov 9, 2004
  • #9
Slow down and follow the links above. All that's required is a way to jumper the diagnostic port and your check engine light or a test light. Alternatively, for about $20 WalMart sells a scanner that plugs in complete with instruction booklet.

How far out were you on HC and NOx? Post the spec and your numbers. If you're close, adjustments might get you there. If you're WAY out and the codes don't reveal a major problem, then perhaps the cats have been gutted.
 
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