I'm a new RX7 owner and very unfamiliar with rotaries. I love my car but it blows a white, very rich smelling smoke on start up. Sometimes it is minor and sometimes it billows. It seems to last a couple of minutes than disappears. Start up is always quick with no pedal - engine revs to 3k drops to 2k and then to about 1.2k - generally little or no smoke. However when I drive away, the white will start billowing in embarrassing clouds. Once this billowing has run its course, the car is well mannered and pretty near perfect. When above idle my oil pressure is 60psi and at a 600rpm idle it is around 45psi.

There is a button on the upper left dash that (I think) disconnects the fuel pump relay causing the car to sputter -- this seems to accelerate the disappearance of the smoke. The engine was replaced shortly before I got the car by an intermediate, short-term owner so I really don't have a lot of history of the modification. I was told that it had recently had a 50k tune up but I'm not sure of the quality of that service.

Thanks in advance for help and advice

 

Oil Control Rings are shot. Do some searching on that topic. Long story short nothing you can do but rebuild. But other than the smoke no real harm except to your cats. My daily smokes and I keep driving it. Still makes good power.

 

That's certainly not what I wanted to hear but thanks for the info. It seems to do this much less when the ambient temperature is warmer and doesn't do it at all on a start up when the engine is up to temperature. Also, it doesn't look like or smell like oil smoke much more like a really rich mixture but I'm not really sure.

 

The amount of smoke I lay varies heavily as well. Sometimes it can sit for an entire week plus and barely smoke at all on startup. Other Times it sits for two days and massive smoke bank. The easiest way to confirm the problem is to rev and hold between 3.5 and 4k RPMs for 10 to 20 seconds. If you start smoking it's oil control rings.

As long as that smoke isn't sweet smelling (which would indicate coolant) it's still probably oil.

 

I'm pretty convinced it's the oil control rings and reconciled to a rebuild. On startup, it typically smokes very little until the Revs build. Then it billows. Then it stops and runs perfectly well.

Two questions:
1) Any recommendations for a good rotary rebuild place in the Atlanta area or a resource for locating such a service?
2) Any idea what the function of that fuel pump kill button on the dash is?

Once again, thanks in advance for all of the help,
BILL D.

 

If someone put in a Fuel cut switch then I would not Rebuild the engine just yet.
Get the Injectors cleaned and serviced.Properly.
That means taking them out and getting them cleaned professionally,not putting Crap in a can in the gas tank.

 

I'll certainly explore the injector issue. If this was the reason for the fuel cut switch, what was the rationale and how was it used?

I did use some gas treatment/injector cleaner and the issue got much worse but is now getting better. Is this significant of anything?

Thanks

 

Fuel injector cleaner juts doesn't Fix dirty injectors on these cars.
That is why I call it Crap in a Can.
Professionally cleaning the injectors will clean them properly.
If the Injectors were dirty and stay open then the OP probably put the Fuel cut on there to cut the fuel so the car would not be hard to start because of fuel leaking into the engine after it is shut down.
This is why I am leaning towards you getting them Cleaned Correctly first.
This would cause the engine to smoke when started if excess fuel was still in the engine.Think about what the engine did not burn,that is still in the exhaust..that would smoke too.

Try something..When you shut down,Turn the Fuel switch to OFF..to cut fuel and let the engine die in it's own..like gag from fuel starvation.
Then when you start it,..start up with the switch OFF,then hit the switch on While cranking.
See if you still get the smoke.

 

Thanks!! I'll definitely try your experiment and will report the results. I've used the "kill button" to shut down the car before and that seemed to have little effect on start up smoking -- but that was just one trial and it lacked your "starve at start up" component.. I'm very interested in trying your method. (Also, the car always starts very quickly and effortlessly -- no pedal, just turn the key and it immediately starts.)

One of the Club members has recommended a rotary shop very close to me, so I'll be getting a more definitive diagnosis of the issue when I make an appointment and have some professionals check it out.

 

"Try something..When you shut down,Turn the Fuel switch to OFF..to cut fuel and let the engine die in it's own..like gag from fuel starvation.
Then when you start it,..start up with the switch OFF,then hit the switch on While cranking.
See if you still get the smoke."

While I didn't activated the cut-off switch when I turned off the ignition yesterday, I did have it pressed when I started this morning. It immediately started, reved to 3k and then died after a few seconds. Second crank brought it to about 1k before it died. I cranked it 3-4 more times with the button constantly pressed and it would start, idle at about 1k and then die. I smoked during the process and for about the first 2-3 miles on a test ride. Then there was no smoke at all regardless of revs. I parked it in the garage, depressed the cut-off switch and it starved and died. I turned off the ignition and then released the switch. I'll wait until this afternoon to restart and will depress the button during this process.

I should note that I'm only assuming that this normally closed button is associated with fuel pump power. A click can be heard from under the dash when it is pressed with the ignition on so I'm assuming this is the fuel control relay.

 

Wait!..you got a rotary shop close to you?
People would kill just to be a neighbor!

 

Brought it to the shop this morning. Good news: They seem very competent and reasonable. Bad news: Oil seal it is. They will do a rebuild and have it back to me in a couple of weeks. Once again, Thanks for the help.

 

What shop did you use? I'm in Georgia as well, would like someone to check out my car too.

 

3 Face Racing in Oxford, Georgia. Their web site is Atlanta, Conyers, Covington, Oxford Georgia Auto Repair - 3Face Racing and Automotive Services