My Big Red Van

Well my father gave me a 1979 G30 van that was sitting unregistered in his California yard for a year. I paid all the past due fines, ($500) and took it to a SMOG shop this morning. And guess what… well you can guess I wouldn’t write if I had it pass. It failed at the HC (ppm)at 25mph registering a 472. Gross polluter. But they only told me that it was mis firing due to possible carburetor issue. And I should take it somewhere else. That was my first indication something was wrong with the place. Maybe. I bought carb cleaner and sprayed the heck out of it, and ran some cleaner through the engine. I did notice a difference in performance. But I noticed after the fact that the oil was 3 qts low. Now it runs alot better. how do I know with out spending more money if it is closer or do you have any suggestions on cheap ways around this issue. The motor is a rebuilt 350ci with a 2barrel carb.

Thanks J.T.

If it was sitting for a year without fuel stabilizer the gas may have starter to turn to varnish and could have gummed up the carburetor. Normal in-tank fuel system cleaner may not be enough to remove the varnish. The only way to know if it will pass the test is to have it tested.

I assume that the problem is unburned hydrocarbons. The sources of the problem can numerous.

If you don’t know when the spark plugs and the air filter were last changed, then you need to take care of those items. It is also very possible that the carburetor needs to be adjusted, and therein lies the problem. Most of the younger mechanics out there have never worked with carburetors, and will have no expertise in adjusting or overhauling one of these archaic devices. My suggestion is to seek out a shop that has at least one mechanic over the age of 45 if you are to find someone who really knows what he is doing with carburetors.

If the engine is also equipped with an air injection system, that may also need work. The same older mechanic who knows how to adjust a carburetor should also be more knowledgeable about air pumps than the younger mechanics.

Change the oil, get some sea foam, follow directions, Run the gas almost out, fill up 1/4 tank and run the gas with sea foam almost out again. Check the plugs, replace if necessary, get a good highway drive before the emissions test and try again, if they will let you.

I didn’t realize that California needed emissions tests on cars 30 years old. One more reason I should stay in the Midwest.

You will have to test your 1966 here in AZ. 2004’s and earlier OBD2 cars get it every two years,the rest every year.

Mileage matters. A new catalytic converter will straighten out the hydrocarbons but you should pull all the plugs and put new AC’s in there. Make sure your 5 and 7 wires aren’t on the wrong plugs after you change them. or even before. Check the vacuum advance too.

Spark plugs and plug wires. Spark plugs and plug wires! Spark plugs and plug wires!

EDIT: (Oh, cap and rotor, too.)