Failed Smog Test?

American Muscle

Registered User
Hey guys I took the SC in for a smog test today and it failed. It looks like there is fuel that isn't being completely burned at idle. So I went out and bought a new air filter, spark plugs, and fuel filter (Just for the fact that it needs to be changed). I cleaned out the throttle body with some carb cleaner just to get any residue out of there. Any other ideas of what I can do to make sure it passes this next time? I'm hoping I won't have to replace the catalitic converter on the car but if it fails after all of this I may need to change it.
 
You didn't say what state you're in or year of your car. It would help.

I just went through NY inspection with my '95 5spd - the two front cats are gutted cause they collapsed on me. Passed - no problem.

The cause of the collapsed cats was same as your's - unburned gas dumping through to the exhaust and it detonated in the cats - blew the insides to pieces. If your cats are bad you'll hear them rattling or see them turn cherry red when they heat up. Also car will run poorly.

Make sure the plug wires are on securely at both ends and coil is giving full spark.

Mark
'95SC 5spd
 
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Oh sorry I have a 92 SC and im trying to get in registered here in California. I don't hear a rattle or anything when the car is running. The car had been sitting for a couple of years in storage so I think i'm just going to change the plugs and see if that helps. I looked at the plugs today though and it looks like you have to have some pretty small arms to get up in there and change them. Any way to get to them from the top or and easier way?
 
Oh sorry I have a 92 SC and im trying to get in registered here in California. I don't hear a rattle or anything when the car is running. The car had been sitting for a couple of years in storage so I think i'm just going to change the plugs and see if that helps. I looked at the plugs today though and it looks like you have to have some pretty small arms to get up in there and change them. Any way to get to them from the top or and easier way?

The testing facility should be able to tell you what part(s) of the test you failed. This will give you an idea of what needs to be cleaned/fixed/replaced. For you SC'ers outside the Great Republic of California, they now smog test your vehicle at idle and at various speeds on a "dyno" up to the legal speed limit. This is to ensure you're not polluting the air more than they say you can at any speed. A few years ago I passed at idle, but failed at freeway speeds...

Good luck!
 
Smog stuff

The station should have given you the VIR showing the failure. Post that and let us take a look. The info there is very helpful and can help get you pointed in the right direction. If you don't know the history of the car, always start with plugs, oil change, filter change (air,oil and fuel), PCV replacement and O2 sensors (if over 60,000mi). It will take an afternoon and a few bucks to get all of this done but it is a good start to being sure you have a nice running car. Also make sure the gas is fresh and the car is thoroughly warmed up before testing. Anyway, post that VIR (blank out any info you don't want us to see) and we'll take a look.
Anthony
 
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Well, since no one replied yet, ill chime in...
I think the HC comes from un-burned gas, though im not certain.

-Nick
 
O2 sensors do NOT live forever, I guestimate 50k to 70k.
Do a google search, on Oxygen sensors, will yeild hours of reading pleasure.
These sensors can cause the engine to run rich when they get old. (high HC)
Also, one time I changed the O2's and it helped the NOX reading.
After replacing O2 sensor, disconnect the battery for a while to Reset the EEC's fuel trims.

Secondly, if you haven't already, remove your MAF sensor
just after the air filter, and spray with electrical contact cleaner
and clean the two fragile little springs (also helps EEC determine air/fuel)
 
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Ditto

Do the basic tune-up I listed above, make sure the engine is warm-hot when it is tested and I bet it passes. You're not that far off.
Anthony
 
Okay so today I did the oil change, fuel filter, air filter, and took out the platinum spark plugs and put back in normal autolite plugs at stock gap. I also cleaned out the inside of the TB where there was a little residue left on the butterfly or whatever its called.
 
If I may, sounds like you are working with fine tune stuff... If the car wasn't running poorly, new plugs, wires, oil, etc might get you a few points on the HC scale.. You need to replace both O2 sensors. :cool:
 
and dont forget to pull both octane plugs, and make sure if they ask you, be like what plugs???.... and pretend you dont know what they are talking about...
 
fine, if u must know, there are two octane plugs, also known as spouts, which you pull them off and u retard the timing a couple of degrees, there is one by the ECM test plug and the other is located by the AC comressor plug....
 
darkstar_one,

Are they electrical plugs, that plug into a connector? I saw one of these dangling by my A/C compressor on my 1990 SC the other day -- since I don't own or have access to a shop manual, had not a clue as to what it was there for -- how do you use them? What exactly do they do, and why are they included on the car -- what is Ford's intent of use by owner? Do you unplug both of them at a time, or can you unplug just one at a time?

Thanks for the reply in advance,

Cammer
 
if you unplug both of them, u retart and lock the timing by 3 degrees, i believe this was for cheap owners who didnt want to pay the extra 20 cents for premium gas, at the ford shops, the ford techs pull it out if the customer complains about pinging and other results of the cheap gas, its just there to retart the timing, its very useful here in california, since we are allowed to retart the timing 3 degrees to allow the car to pass the smog :D

yes they are little electrical plugs, u can pull both of them out at the same time, when the car is running, or whatever, if u do it when the car is running u will see and hear the engine bog down,
 
ohh yeah, some people wire those plugs up when they run nitrous, cause ur supposed to retart timing when u run nitrous so some people wire them up to retart right before they spray the juice!
 
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