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I've changed the spark plugs, air filter, engine oil and oil filter, put in CRC Guaranteed To Pass Emission Test formula two times, drove car really hard immediately before test. In short I've done everything I can think of to have it passed, but it still failed
Someone pointed out the O2 sensor may be bad, so I tested it with voltmeter. Without accelerator pressing voltmeter reading moves between 0.1-0.8, but when I press the accelerator the voltmeter reading moves between 0.2-0.9, staying 0.5 above 70% of the time. I think this indicates that O2 sensor is good, but engine is running rich on fuel.
I went to local auto shop and paid them $70 for diagnosis fee. They said there is a hole in the exhaust pipe, that could be causing the problem. They asked to fix it first and then they'll see if there is any other problem.
Fixing exhaust pipe will cost me around $180. I'm a student, I bought this car for $1100, and I've already invested $900+ on the car fixing things, and I want to be really sure before putting in this $180 investment that this is causing it to fail.
Here is the smog test report:
If its not clear in the picture, the car is failing because of high CO. At 15mph the 1.06 (max allowed is 0.75) and at 25mph it is 0.99(max allowed is 0.63). Everything else on smog report seem to be fine.
This is my first car, and I have no clue about fixing cars. Members please advise what is the cheapest possible way to get out of this smog misery.
If the exhaust leak is before or close to the O2 sensor, it will pickup the false air and the computer will the think the engine is running lean, thus dumping in more fuel.
Depending on the sub model, and what part of the exhaust is failing, you may be able to purchase a replacement component, gaskets, and install it yourself for about half the cost.
I went ahead with the mechanic's advice, and changed the entire exhaust pipe (including the mufler), now he is of opinion that previous car owner drove car with bad catalytic converter, that damaged the EGR valve and their is carbon gathered in intake valves also. So, he need to replace the EGR valve and clean intake valves (I don't remember if that's the right word). Another $620 estimate...
Somebody please reply, if this could be a possible cause, or he is just looping me in circles.
Not sure how a faulty Catalyst could damage the EGR. Sounds off.
Purchase some SeaFoam from the autoparts store. Dump a can in the tank at refill, add some to the oil, and follow the instructions on the can to clean the intake tract.
Now if your EGR ports are clogged, this would cause a lean misfire and high NOx emissions.
The ports can be cleaned there is a writeup in the FAQ at the top of the page on how to do it. Only cost for you would be some simple tools and the kit to reseal the EGR ports after done cleaning.
If the EGR valve is not setting a code for lift, it is most likely fine.
Your Catalytic converter is fine. the reason I say that is because your numbers are not ridiculously high. and like mad mike said you need to clean your EGR ports. heres a PDF link I have used before.
Also besides looking for and EGR code what you can do is when the car is running press down on the rubber part of the EGR valve, if the car sounds like its going to stall, the egr valve is working properly. also after you do that you might as well as remove the EGR valve which is being held down by two 12mm nuts and clean out all the carbon (black stuff) from it
Hello, i used to have the same problem, for somethings of the life i took my car to fix the problem, in the way the guy tha see my car change many parts, the fuel injectors was one of them, but he puts honda civic fuel injectors, the problem was fixed, but really he never realice the origin of the problem, after a few days i started to have other problems, the car stops for nothing, engine doesnt want work, im really curious about it, and i put back the older fuel injectors, and "buala" no problems running, but the emmision go up again, what i do was buy new fuel injector and the problem was completly solved. try wiht other fuel injectors, maybe you have the same case as me
Accord 90, Emission advice needed!
