emissions test failure? what now

[bingroy]

1990 toyota camry. failed emissions test. Nox okay. High CO/HC. Mechanic wants 450$ to rectify problems. Not willing to spend? Anyone knows people in Houston who can help? OR fuel additives that will help?

[Tom 2000]

What condition is your car in?

Has the car been tuned up recently? (New spark plugs, cap/rotor, air filter, fuel injection cleaning, etc..)

My 1988 Camry failed smog several years ago when I still had it.

I tried high mileage oil, ran a bottle of fuel injector cleaner, new spark plugs, air filter and took it back in. A lot of times, this can make the difference.

However, it failed again. The numbers were lower and close the limit, but it was still a little too high for HC (particularly for the idle) and failed.

Then I remembered a trick from years ago. I bumped up the idle (just a tad, like 100 RPM). I also took it in after I drove for a really long time. It passed. There is usually an upper RPM limit for the idle emissions test, so I can't crank up th idle really high, but a little adjustment was all it took.

[bingroy]

Thanks for the tips Tom. My car is in a decent condition. It gives around 20 miles to a gallon, does not have any driving problems, did oil change recently. from reading online I understood that there might be incomplete combustion resulting in a high mix of CO and unburnt hydrocarbon in the exhaust. I have not had a tune-up done recently? Would you guys be able to tell me (a ball park range) of what will cost. At least the spark plugs and air-filter.

Also How do you bump up the idle?

Thanks a bunch for all the help.. really appreciate it.

[Tom 2000]

You should be able to pick up 4 spark plugs and an air filter from the local auto parts store for less than $25. You can do these yourself easily.

NGK or Denso Spark Plugs are all you need. Don't bother with fancy Platinum plugs.

This is the fuel injector cleaner I use. There are others out there that I'm sure works well, but this one has worked well for me. You'll find it at Chevron or most Auto Parts stores.



As far as bumping up the idle, there's a screw near the throttle body. It's not a good explanation, but I don't have the car anymore so that's about the best I can describe.

20 MPG is a bit low for MPG. On my '88, I usualy got 29-30 MPG mixed city/hwy driving. Even my '00 with a 2.2L gets 26 MPG.

Given the low MPG, your oxygen sensor might need replacing as well. They aren't cheap like spark plugs, but still not terribly expensive. They aren't too hard to change either.

You can buy locally, but online, these guys have good prices.

http://www.sparkplugs.com

[bingroy]

Thanks Tom/. My car did need a new oxygen sensor. And now I am trying to clean the fuel injection system. What does bumping up the idle achieve? Can you please explain again how should I be doing it? Where is the throttle body. As you understand I am a newbie......