QuestionQUESTION: I have a 1997 Honda CRV and I recently went to an emission control test which is called Aircare in Vancouver, and it failed because of high carbon monoxide and hydrocarbon levels. Carbon monoxide is supposed to be 9.0 but it was 80.0 which is very high, and hydrocarbon is supposed to be 0.5 and it was 1.1. About two months ago, the engine light came on and when diagnosed, their were two codes: Lean gas/air mixture and a vacuum leak but I couldn't find it, then a month later the light disappeared. I had changed the Catalytic converter, and both oxygen sensors, put new spark plugs, changed the oil, and installed a new original honda air filter. I have taken it to many mechanics but could not figure out the problem. What could it be?
ANSWER: You have a vacuum leak that is causing a lean condition. Any good mechanic should be able to figure this out fairly easily. It is most likely a vacuum leak located after the MAF. One way you can try to find it yourself is to get some carburetor cleaner and spray it around near the throttle body and MAF and see if the RPM's pick up. If they do then you know the leak is around that area.
You can also find a shop that has a "smoke machine". This machine will help find the leak.
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QUESTION: I sprayed some carburetor cleaner on the areas you indicated, and a few more, but the RPM didn't pick up, and I couldn't find the leak. Are there other places I should spray or is it a different problem, Thanks.
AnswerThis is just a quick and easy test to find obvious leaks. Your best bet right now is to take your car to a good mechanic. Find one that knows how to diagnose cars. Many of them really are only good for changing parts. Don't go to the cheapest one, go to the one that can get the job done.
