Emissions testing question

[unklian]

My car just failed the manditory emissions testing to renew the plate.
It's a '95 Caprice,350 fuel injected,motor is stock.

                     Limit        Reading
HC ppm            53            0
CO%               0.29        0.00
NO ppm           380          492

I know that our crappy Canadian gas doesn't help,
but family obligations have prevented me from getting to Buffalo for some good gas.

There is a slight leak on one of the exhaust manifolds,could it suck in enough air to throw off the results?
Or how about the EGR valve ?

Any suggestions?
Thanks.

[unklian]

Just looking at the test results again,they input the wrong size motor.
4.3L instead of 5.7.
And they used a higher test weight than last time. :evil:
Any chance this would cause the system to default to a lower limit?


How difficult is it to change the EGR vakve on these motors?

[parklane]

I've been told that if you put several cans of gas line antifreeze in the tank, and take the car for a good run before getting it tested, it's supposed to help. Don't shut the car off when you get there, to keep the engine hot. Hope this helps.
John  

[58Apache]

Put in the highest octane gas you can find. I understand that higher octane has additives that make it burn longer and more complete.

Run it hard for a half an hour or more .....flooring it many times. If you have to wait in a long line the car will get too cool. I believe that the hotter the catalitic converter gets the more efficient it becomes as well.

My HC's on my 95 Chevy truck with a 5.7L were at 53 also and I think the limit was 50. The guy said that usually they fail by a lot if something was really wrong. He recommended I run it hard for a while to blow it out.

I did that, came back, had to wait in line a little while, but kept it at a high idle.

The second time around it passed easily. Make double sure that engine has been running for a long while before testing. Try to go to another testing location or at least a different bay if possible. It could be a slight calibration issue.