I don't have a complete understanding but it is probable the CAT isn't working.
The CAT has to reach a certain temperature before it begins to work - in the trade it is known as "lighting up", after which the exhaust emissions will fall dramatically and the CAT becomes much hotter as the special materials inside react with the unburned hydrocarbons in the exhaust gas..
The exhaust gas leaving the CAT should be considerably hotter than that entering it.
Until the CAT reaches the critical temperature when it lights up it isn't ready for the emissions test. It is the job of the first oxygen sensor to send accurate information to the engine ECU to ensure there is enough unburned fuel in the exhaust stream to make the CAT light up. Too little and it won't and the performance will be flat and too much will seriously shorten the life of the CAT.
The post-CAT oxygen sensor monitors the emissions, sending information to the ECU which is looking for the predicted rapid drop in emissions caused by the CAT lighting up and therefore the CAT is ready.
Both oxygen sensors need checking as you should now see how they work as a team with the CAT. Purists would say all three should be replaced together...
Run fault codes and check for O2 sensor problems ( ones after the cat converter)
check replace the cat converter/s
SOURCE: Monitors not ready: Catalyst,Evap System, Oxygen Sensor, Egr Syst
Drive it some more. Has the battery been disconnected/replaced recently? The Inspection station should be able to print you out a drive cycle to get the monitors ready also.
SOURCE: 2009 honda civic is struggling to start when its cold
buy a battery that has a higher cold crank amp
SOURCE: 1999 Subruban 1500 LT Failed Emissions Test:
You may have a defective coolant or air temp sensor. These need to be accurate in order for some of the monitors to run. Your going to need a diagnostic scanner to see the data so you can determine what is wrong.
If you had replaced or unhooked the battery just pryor to geting the smog then thats the problem. Just drive the truck for a couple days and you should be fine.
You will still pass the test if you still have 2 monitors not set. California allows that. 3 fail
SOURCE: My 1997 Honda Civic failed
Jose, I don't know if this will give you the answer you are looking for because there are many things to consider here. The exhaust gas recirculation valve (EGR) is one of the main things involved in reducing NO emissions. This valve is controled by the power control module. (PCM) This is your vehicles computer. The PCM monitors the vehicles speed and will command the EGR to open when the vehicle attains a certain speed, which is why the ASM test being done is recorded at two different speeds. At 25 MPH your vehicle failed the hydrocarbon (HC) emissions limit and this could be for a number of reasons. When is the last time you car was tuned up? Old spark plugs, wires, clogged air filters, oxygen sensors, leaking injectors (personal experience) or the PCV valve could be contributing to the results of the test. I guess that the easiest way to go is to tune up the engine replacing the spark plugs, wires, air filter and the PCV valve and don't forget to have the oil changed at the same time. Only then should have the vehicle retested and see what the results are. Should it fail again you may have to consider having the EGR or the catalytic converter replaced depending on what portion of the test fails. If the NO fails I would consider the EGR. If the HC fails then I would consider the catalytic converter. Good luck with this.
SOURCE: Hi, my car today failed
the code is not for engine, it is transmission code, to tell exactly you need a SAAB Tech 2 scaner, It may be the neutralsafety switch . 29 differnt codes for trans. try to move shifter from park to 1. 20 times it may help for now,reset code drive car to set all redines codes, Neutral safety switch is on back order from saab.
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