Hi. This is my first post here, hopefully someone can help me :)

I have a 1997 Altima that I 've had and treated very well over the years.

Over the last month or so it's been acting a little erratic and it seems that my engine is "missing" quite a bit... sometimes to the case where the car will stall out (when braking to a stop after the car has shifted all the way down). My car will start also hesitate switching gears while driving and I will see black smoke coming from the tail pipe.

The weird thing is the time of day that it happens. It only happens during the hottest times of the day (between about 10am and 4pm).

I took it to our mechanic and they couldn't get the car to replicate the problem... it seems the car always acts fine whenever I try to show someone the problem. It's pretty inconsistent and I can't ever really be sure when it's going to act up or not... it just seems to happen most often during the middle of the day on hot humid days. I've never had an issue with it in the morning or at night.

I've been changing the oil, and I even ran about 3 half-tanks of gas + fuel injector cleaner and octane booster (this was after the car started acting up).

I've noticed that my car drips *a lot* of water when the AC is running (I'm assuming condensation). I'm not a car guru by any means... is there a way that this water can make its way into the fuel line?

Any help would be greatly appreciated.

Is your check eng light on? If not, does the eng light come on for a few seconds when you first turn the key on with out starting the engine? Access the diagnostic trouble codes that are stored in your computer. AutoZone and others will access the codes for you. Make a note of the code numbers. You may have a problem with your evap control purge system.

Is your check eng light on? If not, does the eng light come on for a few seconds when you first turn the key on with out starting the engine? Access the diagnostic trouble codes that are stored in your computer. AutoZone and others will access the codes for you. Make a note of the code numbers. You may have a problem with your evap control purge system.

Not seeing a check engine light, no. Is it possible for that system to be messed up without seeing a check engine light? (sorry not a car guru, more of a computer techie)

The light should come on briefly when you first turn your key. If the light does not come on your light is not working. This is one situation where you can have your black smoke condition and the light does not come on.

The purpose of the light is to tell you that there are diagnostic trouble codes stored in the computer.

Have the codes accessed and make notes of the codes. That is where diagnosis begins. Guessing, purchasing, and replacing parts is not economical.

Try removing your gas cap to relieve pressure in the tank when the smoking is happening to see if it makes a differance. Don't drive around without the cap on.

Sounds like a Intake Gasket Failing.. When you take it back to your Mechanic, have them spray Carb Cleaned around the #4 cylinder on the intake side. If idle changes , the gasket is leaking causing your problem.. GL