my foxbody wont pass emisions any suggestions

[wht92fox]

I got a 92 5.0 and i took it for emissions and the hydrocarbons were twice the limit. It has cats but the egr is disconected and the air pump is no longer there. does anyone have any suggestions.

 

[onefstsnake]

I started a thread about this. Search!

Hydrocarbons...Make sure the car is hot before you get it tested.

My HC's were more than twice the limit, just warming the car up and they dissapeared...

Make sure your timing is set right as well. Stock is 10* I think.

 

[PRO50SC]

Yeah, hook that stuff back up. I just went through, all my emissions stuff is on and passed by a long shot. Bigger injectors, blower, higher f/p, intake, t/b, mass air. All aftermarket. I couldn't believe it. I tried to go through once before with no cats and before the mods, wouldn't pass!!

Md is a tough state too.

 

[vristang]

I got a 92 5.0 and i took it for emissions and the hydrocarbons were twice the limit. It has cats but the egr is disconected and the air pump is no longer there. does anyone have any suggestions.

Welcome to Stangnet!

Pull the codes from the computer. You may just have bad O2s. Possibly the cats are aging, and losing effectiveness.
What is your coolant temp? If you are running a 180F (or even worse 160F) T-stat that will make things alot worse. Use a stock stat for emissions testing, and make sure the motor is good and hot when you test. Leave the motor running while you wait for your turn.
I just read today that 50-80% of a vehicles emissions output during Federal testing can be from cold start alone.

The egr should not affect HC too much. I am suprised that you passed the NOx requirement without egr though. Does your state have NOx testing? I've heard some don't.
The air pump may help, but I can't say for sure.

Some fuel additives may help. "Gauranteed to Pass" has been mentioned here before, but I have never tried it.

:Word:

 

[Maryland Stang]

As posted previously you need to check for codes and get that emissions equipment back in working order especially that air pump. My car passes MD emissions with a non functioning EGR but I'm also using a set of very low mileage factory cats and 10 degree base timing to do it. All of the rest of my emissions equipment is installed and functioning.

 

[wht92fox]

The car has new hi flow cats and new O2 sensors, but ill check the timeing and see what its set at. But as for the EGR and the air pump, I bought the car without them on. Do you think that new plugs and wires will help.

 

[Look Its Aaron]

put about 2 ounces of acetone per 10 gallons of gasoline, and that should reduce HC a lot.

 

[RacEoHolic330]

put about 2 ounces of acetone per 10 gallons of gasoline, and that should reduce HC a lot.

The optimum ratio is 3 oz/10 gal. BTW aaron, i'm consistantly getting 2 mpg better with my daily driver. I like this stuff.

 

[DTT92LX]

The cats may not be functioning to their potential without the smog pump. The pump puts air to the cats (as well as the heads) to help reduce emissions. May have an issue there.

 

[Look Its Aaron]

The optimum ratio is 3 oz/10 gal. BTW aaron, i'm consistantly getting 2 mpg better with my daily driver. I like this stuff.

Great! I am glad its working!!!


Try and see how much you have saved. Price of acetone vs mileage.

 

[18mustangs]

The cats may not be functioning to their potential without the smog pump. The pump puts air to the cats (as well as the heads) to help reduce emissions. May have an issue there.

You got it. The catalytic converters need a catalyst to fully break down the unburned hydrocarbons, and this catalyst is the air from the smog pump. If he hooks the smog pump up to the cats he has a much better chance of passing.
Tim