Hey guys, so yeah I'm pretty close to smog time and decided to test it already. The results were the following:

15 mph HC Max: 91 reading 148 CO Max: .55 reading 3.08 NO Max: 768 reading 422
25 mph HC Max: 71 reading 137 CO Max: .41 reading 2.67 NO Max: 649 reading 406

I need some advice on what to do here, mainly with the CO.

The car is an 86 carb camaro.


So far what I have done is EGR, air filter, added the breather valve and tubing with filter as asked by the smog place. In the past year I've changed the O2 sensors, ECM, catalytic converter, and had some vacuum leaks fixed from the seals on the carb, and a faulty water pump. Oil change was done maybe 1500 miles ago.

I did not change the spark plugs, wires, or distributor based on that I bought this car 2 years ago and the engine was supposed to be a rebuilt engine (I expected some newer parts to be on there, but I been proven wrong) and I seafoamed it maybe like a year ago. I didn't get to do it before the smog due to time constrictions.

The smog guy told me based on everything I've done so far, I should get my carb rebuilt and adjusted to the new parts. Two years ago the car had issues with the NO, but now its completely backwards.

I just want to get your opinion based on the results on what you see I've changed and probably needs. All of these changes have brought good results to milage but I had a feeling I was still running rich.

 

Looks like, the plugs in the bottom of the fuel bowl are leaking.

Pop the carb off. Take out the back 4 air horn screws. Flip it over. Take out the screws that hold the throttle plate to the fuel bowl.

Toward the front of the carb, with it sitting upside down, there are some "tower" looking features. Those are actually the material that the passages for the jets and various other things are drilled through. When they drilled the passages, they drilled through from the bottom; drilled a much larger hole, shallow, at the entrance; and when done with drilling what's up inside, spun an aluminum plug in, to plug up the hole.

Fast-forward 30 years. The aluminum the plug is made from, and the chinesium the carb is cast of, are dissimilar metals. The slightest trace of moisture gets on them, and they turn into a little battery. What ends up happening is the chinesium literally gets eaten away by the aluminum, on a microscopic scale. Sometimes you can see it; it looks like white powder in places where different metals touch.

So now, there's leaks all around all those plugs; and on one side, there's engine vacuum, doing its best to SUCK, and on the other side, there's fuel. Guess what happens.

Right: any and all fuel control designed into the carb, is now BYPASSED. Fuel goes straight from the bowl into the intake, without being metered, controlled, or anything else. As a result your car won't pass inspection and drinks gas like no tomorrow.

Seafoam won't help.

Only chance you've got, is to wire-brush the accumulated gunk off of all the plugs (there's about 8 total); STERILIZE the scene of the crime with lacquer thinner; and epoxy them liberally with JB Weld or similar. Bake it in the oven (get as much of the gasoline out as possible FIRST, or your SO will nag you for like months) at its lowest setting for about 2 hours to fully cure the epoxy. Put the throttle plate back on with a new gasket.

The car will probably sound different, smell different, run different, get better gas mileage (maybe DOUBLE), and ... best of all... have a chance of passing inspection.

Wouldn't hurt also, to put a new cat on it.

{spoken as a former resident of Carlsbad / Vista / Oceanside}

 

Thank you sofakingdom for your advice. I'll make sure to try it out asap.

I wouldn't be surprised if its being drown in gas at this point. My milage after the EGR went from 11 to 14 mpg last week, but just my luck it went to crap a day before the smog test. The EGR it had was filthy and I made sure to clean the area as well.

I'm guessing at this point the cat went to hell in the past year with these effects.