I have a 1991 chevy pick up with a 5.7l it failed the test 2
You did not post the odometer reading on the van but base on the year it should has over 85,000+ miles on it.
The most likely source of the high Hydrocarbon (HC) is clogged or drippy injectors.
Change the fuel filter if it is over 48K miles.
Ran two or more tanks full of Chevron gas will help clean out the fuel system.
The air fuel ratio can be off is the air filter is clogged or the mass air flow sensor give incorrect data to the computer (ECU).
Change the air filter is it over 20,000 miles or you can see sunlight though it.
Use CRC Mass Air Flow cleaner or electronic part clean to gently clean the mass air flow sensor.
Change the oil to 20W50 or one grade higher to prevent blow by.
You current motor oil is soak with HC from blow by.
Make sure the tires are at 32 psi
Do the smog test is a COLD morning?
REMOVE excess cargo off the van.
These are little things that I would do.
If the HC is still high at 25 mph then you will need a professional fuel injector cleaning or replace the injectors.
Please post more data on the third smog test on the comment window.
Mar 12, 2009 |
2002 Toyota Sienna