tuff

iTrader: (15)

My beater failed emissons what causes high hidro carbons.

NoGo

iTrader: (2)

Hydrocarbons are unburned fuel. Look to incomplete combustion or cylinder misses as your culprit.

wrencher

iTrader: (2)

What kinda car? How high was the reading >GPM?

Visceral

iTrader: (1)

well......... hydrocarbons arent totally unburnt fuel, just fuel that has not been completely combusted to its raw H2O, CO, CO2, O2, and some NOx's. Poor combustion (not hot enough, not enough oxygen, etc) can crack up the long chain hydrocarbons in fuel, but not completely combust them into the right elements.

Having gotten waaaaaaaay too many old shitty cars through emmissions, HC's can be resuced a great deal by leaning the car out mroe than it is. Also cats are hot enough that they usually crack them, so if you dont have cats, your HCs are usually too high. If you keep leanign the car out, eventually the NOx's start going through the roof, if the station tests for NOx's. THe trick is to find the balance. With the right tools, I used to go around the emmissions station sometimes getting 15-17 tests a day, altering timing and fuel mixture.

Oh... and if you want to reduce NOx you can reduce timing advance as well. I would retard timing aways before going in in the first place and then start leaning it out. (If its a car that you can do all this to)

chris

tuff

iTrader: (15)

Thanks for the repleys my car is a 93 cavaler 3.1 liter.My hydocarbons were 1.05 standarard is .80 i'm thinking dirty air filter sounds stupid but it's looks ruff.I do all the other grubb work and the motor is still a good runner.

2000WhiteZ28

Just do a full tune up, air filter, spark plugs, ignition, ect and try again. You know it could use it anyway.

wrencher

iTrader: (2)

I do a ton of cars in Chicagoland for emissions. i
It is prolly a catalytic converter that will be needed to get it to pass.possible o2 to boot.
This is assuming you got no ses lights & it runs good.
If you want try to take it back thru , but this time b-4 they test it ask them to "pre-condition" it .
They'll run it up on the dyno B-4 testing it.
It might fly.

tuff

iTrader: (15)

I was thinking a converter someone put one on the car at one point.It looks like a cheap pos and it's been on there a while. No ses lights and plugs and wires were done about a year ago. exaust is looking a l'ill ruff and it has that shitty rasp like a flowmaster.

Tom@SpeedInc

iTrader: (5)

You can put a cat on it, but that will only hide the real problems. I would go through a series of tests to deam the cat as the source of an emissions failure. What happens if you have a dribbling injector or bad spark plug?