Recently we’ve had a stretch of some really cold weather in NJ. On some of the really cold days, my S4 TII will just start BILLOWING bluish-whitish smoke everywhere. It really smokes up, if I’m at a red light, the entire intersection will be like a cloud by the time I leave. On rare occasions it comes up from the shift **** too. The car starts up fine and drives fine, and it looks like shutting it off for a few minutes takes care of the issue. No abnormal symptoms besides the smoke whatsoever. Is it just a cold weather thing, or is something busted? It’s only happened twice, both on days that were freakishly cold.

 

Blue smoke is oil, but it's a bit weird that it only happens in the cold. Smells sort of chalky or dusty.

Grey smoke is fuel, also weird that it happens only in the cold. Smells gassy and stings a bit.

White smoke is coolant, which is more likely to be temp related. Smells sweet like syrup.

The weirdest thing is that it seems to be only under certain conditions and not more common. I would check oil and coolant levels and keep an eye on them. Next time there is an incident be sure to recheck and see if there's a change. Fuel is unlikely.

Do you premix by chance? Did you just fill the tank prior to either incident?

 

Nah, I’ve been meaning to use premix for a while but it’s awkward with my state’s ban on pumping your own gas. And my tank was about full. The smoke definitely doesn’t smell sweet, it’s like a charred smell. I thought it was a coolant leak at first but there’s no drips on the ground and it smells foul.

 

If it smells charred, it might be more likely that something is caught on your exhaust. And maybe when you're stationary the smoke is enough to become noticeable.

I'd inspect to make sure there isn't a rodent nest / dead animal somewhere near your turbo or exhaust.

 

Ripped pcv diaphragm? Had a ripped pcv diaphragm, but it would billow smoke upon decel. Possibly check the intake behind the pcv return for oil residue to determine if it’s from the pcv system or the engine.

 

Does this happen only when the engine is cold or when its at normal operating temperature?

 

Only at normal operating temp, it starts up fine and drives without smoke for like 5 minutes before it starts

 

Check underneath for oil leaking onto the exhaust? A little bit of oil makes a lot of smoke.

I bring this up as I reread your original post and you mention smoke “everywhere” and “coming through the shifter”.

 

Update:
I’ve seen some people say that excessive smoke could be a blown turbo. My car also makes a loud “whirrrrr” sound every time I really get on the gas, and is making zero boost, which could also be signs of it. But it doesn’t explain how it’s never smoked before.

 

I was taking a look at it when it was smoking, and it looks like a lot of smoke in the engine bay is coming from near the turbo side:

 

If you have an oil leak near the turbo and oil is getting onto the turbo, its an issue you should diagnose and fix quickly. The oil can catch fire and you can burn the car to the ground. You need to get the car in the air and see if you can see the oil leak from underneath. If you can't see the leak, I would remove the turbo inlet duct and air pump to see if you can get a better look at what's leaking. It could be the oil metering pump, the front cover or one of the oil feed or return lines on the turbo.

 

I found these old pictures of my turbo from when I had my TID off to fix a boost leak. The car was making no boost and was making the weird noise, just like it is now. This is my first RX-7 so I’m not really sure how the fins on the turbo should look, can someone with more experience on this let me know if the compressor fins are bent or not?

 

The turbo itself looks normal to me. I would remove the inlet duct and air pump to get a better look at the oil metering pump and front cover. You should also be able to see if the turbo is wet with oil from a leaking oil feed or return line or if the oil leak is blowing back onto the exhaust manifold below the turbo.

 

I just checked the OMP. It’s pretty wet and it looks like it’s dripped onto the area around it.

 

I also rechecked the turbo itself. One if the fins looks like it’s cut a little bit and there’s scratches on the turbine housing right by the compressor wheel. Is this normal?





the wheel spins fine when I grab it from the center and spin. If I push my finger onto the actual wheel and spin, it makes contact with the housing.

 

Another update: there was a good amount of oil stuck to the pipe in the piping to the intercooler. Anyone know if that relates to the zero boost and the smoke?

 

Oil in the piping after the compressor can be from pcv or the turbo seals.

oil in the intake before the turbo is from pcv.

that should help you diagnose.

Years ago, i had plumes of smoke out the tailpipe on deceleration. It turned out to be a ripped pcv diaphragm.

yes oil in the intake track can cause smoke, which is usually blue since it’s oil.

 

are there any links to where I could find out how to check my pcv? Couldn’t find anything by searching on here or on fc3spro :/

 

Pulled the turbo out to have a look on the hot side compressor wheel. Looks she’s blown. There was also a bunch of black **** with bits of metal inside the exhaust manifold. No clue wtf this is, but it was probably the cause of the smoking. I just hope it’s not something with the engine internals.