Strange black smoke...

[Block8head]

After the blizzard from the past few days, the car went dead...Battery still have juice in there ,but it went cold after couple cranking..
Went to Autozone got a new battery, still have the same problem...
This time i try to start again with a few pump to the gas petal and it vroommmm. with a cloud of black smoke for a good 30 seconds...
The smell from the smoke is horrible, smell like gas mixture with something that i cant explain...

Is anyone have the same problem like this?

[Pilgrim]

Black smoke is usually gas, blue smoke is oil.

Sounds to me like the engine was partially flooded when it started.

If it's running now, I'd say drive it and see if you get a check engine light. If so, hve Autozone or someone read the code and note what they give you. You can look up the code using Google.

[Block8head]

The car is run fine now, no code, no Cel...
i'm gonna have the dealer flush and rplace CVT fluid and oil change in a few days...

[Pilgrim]

You realize that neither of those have anything to do with the black smoke, right?

If no CEL, you should be OK.

Curious - why replace CVT fluid? Do you have a lot of miles on it?

[Block8head]

Originally Posted by Pilgrim

You realize that neither of those have anything to do with the black smoke, right?

If no CEL, you should be OK.

Curious - why replace CVT fluid? Do you have a lot of miles on it?

i know, and yes sir my have 113k as of today..

[Rstolz]

nigh impossible to flood a computer controlled fuel injected car... The throttle is computer controlled as well. any excess gas in the cylinders after cranking without firing is ejected through the exhaust valves and sits near the cat. I don't know 100% but I do not think the computer will allow the throttle body to open any more than needed during cranking, even if you pump the pedal.

eventually the excess gas now sitting in or near the cat will evaporate or if the car starts might get burned up and expelled as a puff of black-ish exhaust

[Rstolz]

I have noticed periodic hard starting on mine too (not so bad as getting black exhaust though), and chalk it up to a failing cold start valve or whatever Nissan's equivalent is.

[Pilgrim]

Originally Posted by Rstolz

nigh impossible to flood a computer controlled fuel injected car... The throttle is computer controlled as well. any excess gas in the cylinders after cranking without firing is ejected through the exhaust valves and sits near the cat. I don't know 100% but I do not think the computer will allow the throttle body to open any more than needed during cranking, even if you pump the pedal.

eventually the excess gas now sitting in or near the cat will evaporate or if the car starts might get burned up and expelled as a puff of black-ish exhaust

I agree - that's why I was reluctant to offer flooding as a cause, but it seemed like the most likely problem based on the symptoms.

The fuel delivery system should not allow any fuel delivery when the key is off. Unleaded gas evaporates more slowly than old leaded gas, so it is a bit persistent IF something is causing it to be injected.

I'm not sure this is the case, but it's my "best guess". If the problem persists, most likely it means computer diagnostic work to look for the cause.

[DreamCar5683]

It should be noted that defective engine sensors can create a flooded or at least a rich mixture. A coolant temp sensor for instance will enrich the fuel if it thinks the engine is colder than it really is.

However, my suspicion is that you may have had some snow blown into your air intake plenum where you couldnt see it. Just a thought. My advice is the same, though, drive it until you get a CEL, if you ever do.

It was probably a fluke.