Car engine emissions..

[Eli]

Originally posted by: Insane3D
Ahhh...so nice to live in a state with no emmission checking. Catalytic converters....hmmm....what are those?

 

[element]

My 88 chevy needed a new MAP sensor to pass emissions. (manifold air pressure sensor) It was running too rich without the sensor, with a new one it runs much leaner which not only helps with emissions but saves fuel too. Not to mention it seems to accelerate better now too. I also put in a new O2 sensor myself on it. And man those are a bitch to remove.

Well worth it though the way it runs much better now. Just to let you know, it may not be the cat that needs replacing. Unless you've been running rich for years and burnt the hell out of the original cat.

 

[element]

Originally posted by: Eli

Originally posted by: Iron Woode

Originally posted by: Vic

Originally posted by: Sukhoi
From what I have learned, having a completely warmed up car is important for lowering emissions. My dad (who got the car tested today) said that he drove the car to the E-Check center (about 10 minutes away at highway speeds), turned the car off for a few minutes while he waited, and then went and had the test done. Can I assume that the cooldown from having the car off a few minutes was enough to increase the emissions atleast somewhat?

Yes. The cat had not warmed up enough, and then had cooled down when he turned the car off while waiting. The testing stations in my area have signs posted that say that you should not turn off your car while waiting, as it can cause you to fail the test. You want that cat to be grassfire hot for testing.

I don't buy that for a minute.

My car's test: http://forums.anandtech.com/messageview.cfm?catid=38&threadid=1315693&highlight_key=y

it was done after my car sat for about 35 minutes. My cats (4 of them) were probably quite cool by then.

What do you mean you don't buy it? It's a fact that the cat needs to be hot to operate effectivly, especially if it's old.

The emissions testing facility is supposed to run it till it gets hot again.