Took my 1987 tercel for emission tests and it failed for the 2nd time. It has very high Hydrocarbons (HC) in the idle only. Anyway I can find the problem or replace a part?
I hope this is the right newsgroup.
ANy help is spreciated.
I'm sure your local Toyota can find the problem and correct it for you.
mike hunt
fl>
The car is worth $800, and I don't want to pay 100 to just find what the problem is.
Thats why I am asking for help here.
Under penalty of losing my 'connection', one mechanic (who performs emissions inspections) recommended advancing the timing slightly and using
93 ocatne gas before going into inspection. Make sure the car is fully warmed up before having it tested.
HC is unburnt fuel so the engine is running rich at idle. IIRC, that was around the time the Tercel either had an electronic carburetor or was just changing over to fuel injection. If it is fuel injected, you can try a container of fuel injection cleaner, either the one supplied by Toyota dealers or Chevron's Techron product. Follow the instructions on the container, then try Hachiroku's recommendations.
It is carborator
Shahin
Late 80's Tercel carbs were not the most reliable fuel delivery system developed by Toyota. Make sure the air filter is relatively clean (see if you can shine a light through the air filter element), drive it on the highway for about 30 minutes before you take it in for a re-test.
Toyota
HC is unburned fuel so the engine is *misfiring* at idle. The OP apparently passed everything else (CO for example) so he is misfiring, not running rich.
It uses the POS variable venturi carb that noone including myself can consistently fix every time. Chances are that if the cause isn't vacuum leak or secondary misfire related, then it's probably a control valve around the POS carb, followed by an obstructed bleed circuit or venturi slide problem internally. My opinion is that any carb problem on a 1987 to 1990 Tercel isn't worth fixing. That opinion gets more strong every year.
Toyota MDT in MO
The OP
Oops! Another brain fart from Ray on the mixture thing! Asleep at the keyboard.
I remember sitting in on a class on the variable venturi carb and thinking that it was going to be a constant source of comebacks since it was a PITA to calibrate and there were too many things that could go wrong with it.
Actually I have the same car :-)
And back in 2000, I too failed emissions. But I was able to get it to pass - with flying colors!
Check out the before/after emissions results:
HC (ppm) CO (%)
Limit: 220 1.20 Before: 267 3.05
I have an 85 carbourated Corolla that starts to run really rough when cold about every 5 years. A can of carbourator cleaner inside and out, followed by WD40 on every moving part I can see is my solution.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.