So, m42 failed cali smog

[series88]

So my car failed smog today. I just installed a different cat since mine was dead. Cat installed is from a car that passed smog. Hoping to get insights on what to do.

On to the results

[Danny]

You need to drive the car harder and really get that cat HOT before you get put on the rollers.

[series88]

Which i did. Revved hard and drove maybe 5 miles or more

[Gregs///M]

New o2 sensor should do the trick. Make sure you have no vacuum leaks too.

[jlevie]

High HC & NOX can be be from lean partial misfires. In this case, since the numbers are worse at the low speed test the first thing I'd do would be to smoke test the intake and fix the leaks it reveals. If the O2 sensor has 100k (the replacement interval) or more on it replace it also.

[CB-M3]

I failed NOX recently. Replaced CAT and O2 sensor. Fixed all VAC leaks. Passed. Drive it for like an hour before taking it in. Usually when it's High NOx it's the Cat or O2 sensor.

[jlevie]

I failed NOX recently. Replaced CAT and O2 sensor. Fixed all VAC leaks. Passed. Drive it for like an hour before taking it in. Usually when it's High NOx it's the Cat or O2 sensor.

High NOX and normal HC will always be failed catalytic converters. But high HC & NOX can be misfires from lean mixtures. That could also be from bad catalytic converters, but before replacing those you first want to make sure the engine is running correctly.

[2761377]

if by chance you find an extra, new, factory cat for that car, please let me know. i called my local dealer and then steve@blunttech and they are NLA, not to be found in north america or germany. neither are the turner aftermarket units.
thanks
robert w.

p.s. spend way more time getting the cat hot. 5 miles is like only 10% the distance needed.

[amcink]

Here you go¡ i paid $225 installed

http://www.magnaflow.com/02catalytic_converters/02product/displayuniversal_pre.asp?universal=36004

[deutschman]

I had high NOX, and it turned out I needed a good valve adjustment. Make sure your spark plugs are all gapped correctly. Thats all I can add to what others have already said.

[series88]

Thanks for the input guys. I will look into all this. I really want to get this car running right. And yes, I definitely feel a misfire on idle.

Also, I forgot to mention CEL turns once in a while when undergear..

[Dj Buttchug]

after you fix all the drivability issues ask the smog tech to speed violate the car. Itll get the cat nice and hot immediately before another test is run. Sure you can go and drive youre car for an hour before the test and burn up all that fuel but as soon as you go in for a test and the car is parked waiting to get on the rollers it begins to cool down, yes you can leave it running but the cars not under load and the exhaust temp is lower.

Just ask for a speed violation before the initial test. Any tech thats not a total douche will know what you want and they will do it.

also, california sucks dick
that is all.

[series88]

I agree with you bchug. The car actually sat for a while. This is not my normal smog guy. He was a tool and basically sat there on the phone while cars were waiting

[series88]

So looks like cat is bad. 02 sensor was replaced, timing is good, vacuum leaks checked (none found), spark is good.