ive been putting this off for some time but looking in my rearview mirror tonight just reminded me that i should address this problem. i would assume that its NOT the turbos cause id expect smoke at various RPM's if that was the case. any thoughts guys?
thanks, heath

 

Maybe it should be standard procedure to list your car's mods, a little history, last known compression, etc. kinda like a tech support form, that way the original poster actually gets the feedback he wants quicker because people don't feel like asking the same basic questions over again; whats your mods, mileage, compression, any visible leaks, etc...

I would consider responding if I had more info

 

not a problem... i usually do the 'list' but it slipped my mind.

anyway i have a 94 with 89K on the stock motor. stock turbos (wastegate ported). DP/metalic cat/cat back. everything else is bone stock. no leaks. silicone vacuum lines, new intake gaskets, secondary turbo doesnt come online sometimes. ive never checked compression (but i own a compression tester)... im scared of what ill find but its still running and pulling pretty hard (when the secondary decides to work). havent checked boost pressure... i have a gauge but i havent hooked it up yet . basically i have too many projects and not enough time to devote to my 13b (i have another FD thats a 20b project which eats all my time and money... so this car gets little attention, and is not driven that often ) anyway that should be enough info to get you started.

-Heath

 

^

 

Any fuel mods? The fact that it only smokes over 6.5k and your secondary sometimes doesn't work, it just makes me wonder if it's not running too rich whenever that happens? Any smoke at idle? If so, what color? How are your plugs looking?

 

no fuel mods... i havent touched the fuel system at all besides changing the fuel filter.

YES, it smokes at startup. its burning oil (blue)... if i give her a few revs it stops after 10 seconds or so. also, the smoke at 6.5K+ is oil as well (blue).

i changed my plugs and wires 5K miles ago... last i checked they looked, well, normal... but i can check them again. im pretty sure its not an ignition problem but you never know.

 

I would tend to think that if your turbo seals are leaking (but not profusely) that there isn't enough oil pooled up inside the intake tract to burn oil "all the time". It might take some major intake flow to get enough oil pushed down the tract and past the TB into the engine to begin burning enough to start puffing visual amounts of smoke...

 

If you secondary boost sometimes doesn't come on, I think it would be good to have the boost gauge hooked up and see what it does when it "does" come on and when it "doesn't" as well as when you get smoke or not at 6500 rpm. Aside from that, a compression test would be good too, you never know, maybe one of the rotors is low and causing a problem there. After that, test the check valves/solenoids but I don't know if those would cause smoking, I don't think so, but it might be why the secondary doesn't come on sometimes... so the smoke could be a different problem not related to the turbo...

eh, more diagnostics...

 

yeah im nearly certain theyre not related problems. usually after a few tries on the turbos everything works fine. again i think its a separate problem. the smoke at startup and past a particular rpm would suggest some internal engine seal or oil valve problem to me.... thats MY best guess

 

dood, you got alot of cars. I have a '90 bmw 525 in very good condition as my DD and I'm still hesitant and picky about getting an FD.. first one I had for 3 days .. then the coolant seal and oil seals blew AFTER I had it thoroughly inspected by MazdaTrix... thats another story. Last time I take there word on "yah, its ok for a while, maybe a rebuild within the next year" .. lol. That was before I knew much about FD's. Had I known what I know now, I would have left the car with them and not driven it home. I think the rear rotor was all under 85 psi. Front rotor was like 85-90... I was like "is that bad" .. they said "its not great, but should be drivable"... I guess they had too much work.

Coolant pressure dropped a bit just within 15 minutes .. I didn't know it's supposed to set overnight, but they should have.

 

bump for any other thoughts on possible causes

 

Sorry this doesn't answer your question, but were you getting creep at all w/ your metalicat before you ported the wg?

 

unfortunately i did them both at the same time

 

my experience previously is my turbo manifold is starting to crack..
and also my turbo shaft is having some free play... my lubes are loosing quite fast.. my intake pipes are oily...

which means my turbo bearing is not healthy...

try taking out your intake hoses to see if any excessive oil in them... do a shaft play check.. and also check ur lube more often to see if excessive loosing of oil.. some loosing is normal.. but not excessive like from Full to Medium in a week time of normal driving and some hard driving.

 

im not loosing oil much more than i should be and the piping is not overly oily... little residue but by no means is this problem turbo related.

anyone else? rotor oil seals = rebuild. could it be anything else?

 

up

 

I've been reading up on Turbo rebuilds on the forums and symptoms of leaky turbos and what NAN777 said is pretty much online. So, aside from checking the intake piping, take a picture of it and post the pic if you want more opinions if people think the turbos are leaky at all. Check for leaky injectors... maybe take photos of spots around the turbos... someone might spot something you don't.

Also, what are your compression numbers? How about results of a coolant pressure test? And what does the boost gauge readings look like at all rpm's.

Some pics and numbers would get more responses I think ...

 

dude its not the turbos. there is basically NO oil in my intake pipes, and leaky fuel injectors wouldnt cause blue smoke...

 

Just goes to show not too many people really understand these engines Ramy. Hi rpm blue smoke is the perfect indicator of faulty rotor control o-rings. The centrifugal forces from the higher rpm's cause the oil to blow past both oil control rings and into the combustion chamber. It's rebuild time my friend.

 

thanks thats what i needed to hear (although i didnt want to hear it haha). assuming that, would it be a safe assumption to think that the smoking at startup is also being caused by the rotor oil control rings, but in that case since the motor is cold (w/ rings already out of spec) the control rings are slightly contracted causing blowby at startup (before everything expands 15 seconds later). either way, its probably better to rebuild now than wait till i overheat this core or throw an apex seal and have to replace EVERYTHING haha. can i consider the upcoming rebuild a "reliability mod"?

-heath

 

it would be interesting to know what your current compression is that the rest of us would have something to go by ... in addition to blue smoke at high rpms ... to completely indicate an o-ring failure for future reference. maybe thats too much effort tho

 

consumption as far as oil... i dont know. standard. it only smokes for 15 seconds at idle and will only smoke if i take it past 6500K+ . so my oil consumption has been rather usual. i have a strange situation where my o rings a "failing" but have not yet failed, and only "fail" under certain circumstances. so data from me would be useless. youll surely notice the constant plume of blue smoke coming out of your exhaust before you notice how much oil its eating

 

This is a cheap rebuild do it now if you have additional transportation.

 

by all means do i have additional transportation haha its time i dont have . BTW t-von hows the 3rotor going? mines still on the engine stand. if i hadnt bought another chassis and all the associated parts already this story of a bad oil seal would have a silver lining

i might try the rebuild myself, but i dont have all the tools to spec out the parts for clearances etc. i could get them and follow the specifics in my rebuild video or i could just buy a new set of seals and blindly install them. i wish i had more time... neither approach sounds appealing
-heath

 

Take the car to a smog dyno, you can probably rev it up to 6500rpm in 1st gear on one of those (I think they handle up to 35mph or so). On the smog computer they can analyze most of the chemicals in the exhaust and tell you if some are way off the charts. It might help narrow down the possible cause... Good luck!