Air car

1992 Hyundai Sonata can't pass clean air test.
Hydrocarbons too high.
If the car is a visible coal-burner they don't even test it, this one
gets tested and fails. It has not gone 20km - 12 miles since the fall,
only to the test facility and back.

What are the obvious things I should look to?
I figure since the converter is 12yrs old I may get better results if it
were changed but would that be enough?

How about plugs, oil and hi-test gas? Would they help get emissions in
range?

Thanks

gkw

 

1. Be sure the car is properly warmed up before testing.
2. Check to make sure the thermostat opens properly.
3. If the oil looks like it may be dirty, change it.
4. Do you have a check engine lamp on? If so, check the error code.
5. You may be burning oil. Does your car puff blue smoke on initial
start or after long periods of idling? If so, your valve stem seals are
probably leaking.

 

If all else fails, try putting a quart of denatured alcohol in the tank
before having it tested.