I had a problem start with my 93 RX-7 this morning. I was running at high RPM's, when I noticed a white smoke screen behind me, coming from the exhaust. The smoke stopped in just a few seconds when I slowed to a coast. I then tried to make it happen again, my favorite method of diagnosis.

It seems to only smoke when I run at high RPM and then let off the throttle. A short burst of white, oil smell smoke from the exaust.

I think it may be a turbo problem. What's the easiest way to know for sure, and figure out which turbo is the problem?

The car is bone stock under the hood.

Thanks!

 

rev it up and put a damp towel on the exhaust then smell it, if it smells sweet its coolant and your water seal broke

 

Either one of your turbo is leaking oil at high rpm or its your engine

 

Could he also be leaning out?

 

is it under boost and high rpm? the pcv would be a place to start. prepare for the worst and look to the simple first. any coolant loss? did it just start?

 

Haven't noticed any coolant loss. Smoke smells like oil smoke.

Just started today. still runs and idles fine otherwise.

Seems to happen when under boost and high RPM's and I abruptly let off the throttle. Short burst of smoke. Seems like vacuum may be sucking oil into the intake manifold through the turbo or somewhere else.??

Does that sound possible?

 

i would check the pcv check valve first

 

check your rear bumper, if you have oil spot...ur turbo is pooping down into your motor and casing the motor to burn oil inresult of white/black? smoke.

 

I would check pcv valve and also look in intercooler/piping. I think the pcv may be checked by taking off the oil cap and doing a run - no way you could build crankcase pressure with the cap off. Though I dont know if you would have any oil coming out of the filler tube.

Then just check to see if you have oil in the intercooler system. If your turbo seals are letting go you will have a bunch of oil in there.

Shawn

 

I had this happen after my apex seal went out as well.

What ended up being the problem was the oil control rings on the rotors were worn out and the iron housings were warped to the point that High RPM's throttle chops would cause a bunch of oil "blow-bye" and you get your NASCAR style engine plume of oil!

The PCV is a likely suspect if you are tracking your car and cornering really hard..( Way harder than you would on the street, Unless you drive like a jackass on the roads) Mostly hard right handers.As the oil tries to climb out the filler neck. The more likely cause in my mind is the rotor oil seals/control rings.

FWIW: mine would happen at around 7k RPM throttle chops.

 

BigIslandSevens - I first got the smoke during a hard right hand turn while driving like a jack ***. 6am on the way to work, couldn't resist. And like you described it happens any time I let off the throttle in the upper RPM ranges.

How does the oil get burned during the hard right turn??

 

It gets burned by the oil climbing up the filler neck in the right handers. It (the oil) then goes thru the PCV solenoid and thru the vaccum lines to the UIM. OR it goes thru the lines to the primary turbo inlet and then gets sucked thru the intake and IC piping. ( Hence why you would see oil puddles in the pipes)

I to had it happen to me first in a hard right hander driving like a jackhole as well. But after that it kept doing it at high RPM's. I think it was just a coincidence that i was turning and chopping throttle after the turn at around 7K. I had already diagnosed the seal cracking so I knew that it was going. It just went for good i guess. The engine had been rebuilt 3 times before I got to it.

And not to scare you but none of my engine is reusable. A cause more from shiity rebuilds in the past than anything else.