I'm hoping someone points out something that i haven't checked yet, but I'm pretty sure its oil control rings according to researching. Smokes on startup, and stops when warmed up. It was random at first but now smokes all the time on cold starts. I initially thought it was the turbos because it was covered with oil on the primary side. pulled the turbos off and the exhaust ports didnt look excessively dark either. Swapped new low mile turbos in, and still leaking. PCV is new also. Seeing as it is so common, I'm going with the rebuild. This will be my first FD rebuild. I've been a FC guy for 6 years before jumping to the FD 2 years ago. I am a bit disappointed that the Oil control Rings are bad with 99k orginal miles that has a max compression of 120psi and even bounces on a three faces and both rotors. I took care of the engine for 15k miles and it still runs strong just has cold startup. I've had S4 and S5 T2s with 185k, 210k, 190k miles, and they never had any oil control ring failures, but I do understand FDs generate more heat. Out of 8 FCs only 2 needed a rebuild, my first one due to cooling seals at 120k went out from overheating, and the other one I bought with blown apex seals from detonation from previous owner. Besides, that Rotaries have been good to me. Oh well, I guess its time to pull the motor out and start replacing things. Putting in 99 spec or BNR stage 3 Turbos for sure before that motor goes back in.

 

You could have tired/leaking oil injectors. What color is the smoke?

Failure of the oil control rings causes excessive smoke above 3500 rpm. Simply hold the RPM at 4K and if the car smokes like crazy then that is the problem.

At 99k I would expect a coolant seal to be on it's way out any time.

Oil at the primary turbo can easily be blow-by being sucked in from the oil filler neck. The nipple that points down is routed directly to the primary turbo inlet. The other nipple on the inlet elbow is to supply filtered air to the oil injectors. If you have a failed oil injector(s) which is allowing oil to flow backward into the vacuum line, this will also cause oil build up in the primary turbo.

 

Its oil for sure. Smells like oil and is blue. Im a master tech and work in a shop, so I definitely know what blue smoke is. Coolant seals are good, doesn't overheat. I'm consuming more oil too, so it's oil for sure. No smoke once it fully warms up. Rev to 4000rpm and redline then decel, no smoke. I was thinking that the control rings would expand from heat when it is fully warmed up. Is there anyway to test for bad oil injectors besides pulling them out? Also would leaky injectors smoke all the time or just from build up overnight? And how common and what mileage does the injectors usually fail? Thanks for the help.

 

My oil injectors had failed at ~40k miles. The test for them according to the FSM is to be able to blow through them, but not suck. I would not recommend using a mityvac to test these. The breather line for these enters into the primary turbo inlet as described by Banzai Racing. Honestly, you could do the blow and suck test on that line, but to replace them you have to pull the UIM anyway. If you orer new ones, they are ~$50 from Ray @ Malloy. If you're too cheap, remove you oil injectors and "punch" the rubber stopper out of it and add a check valve externally to it.

My Rx7 also smokes on start up. It smokes a light white for a period of maybe 2 minutes before completely subsiding. This is from condensation build up in the cat and the exhaust. The exhaust gets very hot and as it cools down it condenses water. The easiest well to tell its water is if it does not smoke right away on start up. I'll start my 7 stone cold, about 1-2 min in it will lightly smoke white smoke that dissipates quickly, then completely stop after about 2 min. The smoke also smells like steamy water.

Matt

BTW I see you work at a shop in Fresno. What shop? I used to live there before I joined the military.

 

Thanks for the input Matt. Yeah, I know it's not coolant seals for sure. I had that before on a FC and it would be white smoke. So your oil injectors failed at 40k? Damn, that's pretty early. I never had oil injector issues in my FCs besides the line or OMP itself. But I guess it's a bad design on the FD. I hear the 94-95 are more prone to failure too? Is that true? Also, did you have similar smoking symptoms when you had bad injectors? If imma take the oil injectors off I'm just gonna put new ones with SS oil lines on since they are prone to failure. I'd really hate to rebuild the motor since compression is great and it is stronger than my other FD with less mods. But if imma tear it all down, I'm gonna do it all, probably new rotor and housings too. But yea, that's cool you used to live in Fresno. I'm a master tech at a Pepboys. I know Pepboys sucks but it's hard when u got a DUI. Planning to open my own shop in 1-2 years. Just saving up really for the first hard years. Anyways, let me know what ur symptoms was like. Thanks Matt.

 

The difference in the design is dependant on wether it is a boosted application or not. The check valves are in place to prevent the combustion chamber pressure from scavenging or rejecting the oil. If the valves fail, they can ingest more oil during vacuum, and back low the oil through the breather during boost. This causes a loss of lubrication under boost. Very bad stuff. I replaced my nozzles roughly 4k ago and I still experience the light smoke on the first start after a period of time (most usually a full 100% cool down). Premixing is ALWAYS a good idea. If your smoking is only at first start up and clears up, I wouldn't be too worried. If its smoking at high rpm or under the conditions as stated by banzai racing, I might be concerned.

Matt

 

Yea, I think I'm going to get some new injectors regardless. Hopefully that's it. And how much is light smoke? And how long does it last? Yeah, I feel like the oil rings are good because it doesn't smoke at high rpms once warmed up. So well see once I get in there and test them. I just need to figure it out so it doesn't clog my cats and burning excessive oil is a qt extra I don't need to be buying every month.

 

If I was at home I'd get you a video. Unfortunately I'm out of town for the next two weeks though. Its a thin white smoke that begins roughly 1-2min after start up. It will lightly smoke steam for about 2 minutes before it immediately subsides. This is even prior to full warm up that it dissipates. This is not by any means THICK WHITE smoke. Thick white smoke that starts and does not go away is coolant jacket o rings. Check out youtube for some videos on bad cooling seals.

Again the reason why it likely smokes is from condensation build up in the exhaust and the cat. The water is simply boiling out of the cat as your car warms up.

Matt

 

Why are you worried about a little smoke on start up? Worry about it when it smokes all the time.

 

Hey I remember when i purchase oil injectors back in late 95 into 96 the parts guy told me that mazda has new part for oil injectors and supposed a better design. Anyway not until recently i came across a 2001 engine and deceide to compare it to one's I had brought new and to my surprised the 2001 oil injectors has a larger openning, so if u can get hold of someone parting any late seris 8 engine u might want to jump on it, I look at it as better Lubrication for housing.

 

Oh I thought u were talking about blue smoke. I'm not worried about coolant seals. I've had that on a FC before. My Fd holds pressure and doesn't overheat.



I'm worried because it smokes excessively thick on startup til it starts warming up. It ain't normal. That's why I'm worried. I like my cars running perfect, and besides it will clog cats.


Ill look into that. Thanks.

 

If you want it perfect than buy a new engine or rebuild it. Any engine with 100k miles,regardless if it's a piston or rotary, will burn oil. Just drive your car and don't worry about it until you see a smoke screen in your rear view mirror.

 

Not really actually! A lot of my cars including rotaries didn't smoke. May not be perfect but close. Not gonna rebuild it unless its necessary. Engine runs and idles great. Just initial startup. If you can help, I'd appreciate it but if you can't help, then that is cool too, I'd appreciate it. Thanks bro.

 

Ordered new oil injectors from Mazda with my wholesale discount of $31 a piece. I'll give an update once they come in and I get a chance to work on them Thursday.

 

Interested in the results !

 

Me to .

 

Any updates? Thursday has come and gone

 

UPDATE: Finally I found time to work on my car. Been so busy at the shop and other cars on the side. I also finally came up with enough money to pay for all the new solenoids, fuel hose kit, fuel injector reconditioning & tests, check valves, gaskets, vacuum hoses. Lucky I get wholesale discount from Mazda, but $1500 later and its all been installed. The car used to smoke cold until it warms up to about 60-70 deg c. I don't know if its just residual because I only started it cold twice. But either way, it only smokes for about 5-10 sec only and then clears up. and its not as thick as it was before. Been around rotaries long enough, but I guess I learned something new. Sorry part is I actually don't have enough to do the whole cooling system at the moment so I shortcutted that. 6 pulls later and the hose from the rear housing to throttle body bursted on me, so now I'm gonna do the whole cooling system. I guess the 7 will be down for a little bit longer. But at least it doesnt smoke crazy anymore. I hope it works out for the rest of yall. and thanks to everyone for the info and help.