QuestionQUESTION: Ok as far as I have understood, the black smoke problem could be an injector working improperly right? I changed the plug and wire, all 4 are new. The other day one mechanic says the idle air control needed to be replaced as it was causing the malfunctioning, another one says it might be a sensor? is there a way i could find out the problem with your help and myself as I have spent a lot money trying to repair this car and I havent been able. If there's a way to check what you told me on a DIY basis, what it might be?
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what is over rich condition?
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where r they located? the fact is I dont want to spend more money on this car. It has new engine, transmission, alternator, distributor but it still has problems. Why I was told by Nissan dealer it was the distributor? then I have another mechanic saying it is the idle air control. and another saying it is a sensor! I'm going crazy and broke with so much advice but none is accurate.One of the spark wires is pushed from time to time. if not mistaking it is the secon cylinder one
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My car is working like if one cylinder is not working. There is a lot of black smoke coming out but itgets to a time when it gets stables and runs well. I have changed distributor as i was told by Nissan dealer ëxperts" it was the problem, but it still continues, what can I do?
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Luis,
Black smoke should relate to over rich condition. I would check the fuel pressure and the injectors to see if one or more is defective.
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Luis,
If a plug wire pops off it could lead to an over rich condition. But, not where it would smoke. If a wire keeps popping off I would change that wire and lead.
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Luis,
Over rich condition means that you are getting too much gas in the engine either through a stuck injector, a bad fuel pressure regulator, or you are not getting spark to a specific cylinder and the gas that enters the chamber is not being burnt. I lean towards the first two since you say you have black smoke. That means you really have alot of unburned gas.
ANSWER: Luis,
Before I spent a dime I would pull the plugs and look for one that is really black. If the car idles fine the idle air control valve is fine. If you find a black plug among the bunch that is the hole where the injector is defective.
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QUESTION: Hello there, I would really appreciate your help. I changed the mass air flow censor and car seems to be ok now. The missing cylinder problem has not shown since the change. There is another issue that worries me and it is related to my windows. You know there is a like a master switch (if it can be called so) on the passenger window side. This switch, when on, does not allow other people's window to be open. The problem I have is that when that switch is off, the right rear window begins to open it self and there is no way I can control it. Do you have any idea what might be causing the problem?
Thanks
ANSWER: Luis,
If you are talking about the master switch on the driver's side door and the window lockout function allows the rear window to roll down, part way when the lockout is off. Then, I would think the rear window switch is defective and needs to be replaced. Not the master on the driver's side door.
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QUESTION: thanks I will go and buy one at a junk yard tomorrow. U know my car is a 1993 Nissan Altima, with more than 225000 mileage. what is the average mileage it will make per gas gallon? it is doing only 150 with a full tank which is almost 14 gallons. What can I do to improve mileage per tank
AnswerLuis,
The car has to have a problem with either timing or the fuel pressure regulator. You should be getting 20 miles per gallon or more and not 12 miles per gallon. Anyway, I would be looking at a tuneup and make sure the timing or the fuel pressure is within specification.
