Yikes!! Thick White Smoke... engine shot?

[Eikon]

My brother's car:93 240sx Convertible. Stock KA24de engine.

Long story.. you can skip to the bottom 1/3 to get the idea and what I'm asking about. Thanks!!!

Bought the car about a year ago with a bad auto trans. Started it once or twice but couldn't drive it around. It sounded like it had a pretty bad timing chain guide rattle. Topped off the oil and the timing chain rattle got better.. but still there.

Let it sit over the winter and through this summer. Engine seemed to be just fine for random startups.

After sitting for a while it developed a miss. Pulled spark plugs to find out it was cyl. 4. Swapped fuel injectors from 4 to 3 and repulled spark plugs... the missed moved to 3... So bad fuel injector.

replaced with new injector and it seemed to run ok. Not great, but wasn't missing anymore.

After 5 spd swap, drove it about 40 miles from shop to home. Seemed to run ok.

Next time it started with a loud rattle (thought timing chain guides again), topped off oil... didn't get better!Started it again a few days later... same loud rattle. This time it started spewing heavy white smoke.

Last night we tried to drive it a few miles to a buddies house to diagnose and compression test it... Didn't make it!!! The car died and is now sitting in a parking lot of a conveneice store.

I can get it to start. But it smokes a ton... like you can't see the cars behind you!! The smoke is white and smells of coolant.. but I don't see oil in the radiator cap.??

Any ideas???Head gasket because it smells of coolant and runs like crap! But I've never seen that much smoke! It's like we seafoamed it!

Timing chain may have slipped a few teath and the valves may have impacted the pistons... That would explain why it runs so bad and bogs down and dies. But would that cause the white smoke?

Any other ideas??

[elwesso]

Ive seen this on northstars all the time.... Sometimes the head gasket will blow only enough to let coolant get into the cylinders but not enough to cause oil to mix with coolant... Is your OIL milky??? Sometimes coolant will mix with oil but not the other way around (as weird as it may sound).. Plus a little bit of coolant will mix with the oil and make it milky, whereas oil in coolant will tend to coagulate, so if its just a little bit youll just have a blob floating around...

and where are you checking the coolant from? The overflow tank, or actually taking the radiator cap off and looking in????

[Eikon]

The oil on the dipstick looked ok.. but that's not a great place to get a real view of the oil... where should we look... w/out having to pull the whole oil pan off....

I viewed the coolant by taking off the radiator cap after the engine shut down and cooled off a bit. It looked pure green... didn't see any swirl or discoloration.

Sounds like were going to tow it to a mechanic down the street.. he said he'd do a full diagnosis for $40. Compression, leakdown, etc...

I think it's time for an SR swap!

What would happen if an injector was stuck open... say it flooded one cylander.. If you could start the car.. that would clear that cylander out after a few strokes wouldn't it?

My guess is that there is a crack in the head or block. That crack opened up more when we drove it 1/2 hour. Then sat and then opened up even further when we started it up and drove it around the block after doing brakes.

[elwesso]

the dipstick would be as good as anything... a bad injector will make it run super rough and youll probably want to kill youself if it was smoking that bad due to fuel...

actually with an injector that was stuck hardcore open youd have a better chance of hydrolocking the engine... still, it would dump fuel like crazy... injectors dont really get stuck open like that very often, normally its the rail that leaks when you get that much fuel... injectors usually just get lazy and dont shut all the way...

with all the sitting especially during the winter its possible you got some block cracking, however that may be visible..

Your leakdown test and compression test will tell all, thats the first step!