Today I rescued a 90 TGP (all options sun roof, leather and CD) from a low end dealer lot ($500).  It had been sitting there for a long time. It has really high miles though(144000). Supposedly he got it on a trade in. It was slipping slightly unless you really got on it. So he had a transmission shop put another one in it. When he got the car back it smoked very bad.

Therefore my problem. It smokes very bad out the tail pipes. Yes... I have already thought of the oil return hose. I fixed it on my other TGp and it fixed the smoking but it didn't smoke 1/10 th of what this one does. I swapped the oil return just to make sure..and yup still smokes bad enough you can't see the car in back of you and all mosquitoes for 3 blocks die. I even drove it (country road) for about a half hour hoping it was just burning out left over oil from the pipes.

Is there any way to tell if the it is the rear turbo seal or a ring problem. Do I have to take of the turbo to tell? I am at school right now and I wanted to get the smoking fixed so I could drive it to my home town, and my apart complex will B*T*H if I do any thing major in the parking lot.

I would try the vacuum modulator. The car is probably sucking tranny fluid out of the trans and burning it. Pull the line off of the modulator (i have a pic somewhere if you need it) and check to see if there is trans fluid present at the hoses or coming out the end of the modulator.

The best way to figure out if its the rear turbo seal is to elimnate all other causes of smoking.   There isn't really anyway to check without taking the turbo off and possibly apart to see if its leaking. Problem being if anything upstream of the turbo is smoking, it will go through the turbo.

Chris

What color smoke? Blue or White-ish? White-ish with a pungent smell will definitely be the vacuum modulator. Like Chris said it might be pulling tranny fluid straight through and burning the tranny fluid which will cause a mosquitoe fogging that we can use in Colorado!! West Nile Virus don't you know!!  :lol:

As Chris said...pull the vacuum hose off the Vac Modulator and run the car. The smoke should subside relatively quickly.... 8)

Yes the smoke is bright white. But there was also lots of oil backing up into the intercooler when I changed the drain hose.

I went out today and pulled offf the vac modulator hose and let it run about 5-10 minutes.

Was it supposed to stop that soon? It doesn't even seem like it slowed at all. Are you shure by pulling off the hose it will fix (short fix) the smoking problem. Could the idiots at the tranny shop have put it in wrong thus allowing fluid by somewhere no matter what?

I am still confused though..... how could tranny fluid get into the exhaust streem. I must not completely understand how a vacuum modulator works. Please enlighten me.

Tim

The tranny fluid does not go direct to the exhaust...it actually is drawn up through the vacuum line that is connected to the intake plenum and then ingested through there. So it actually burns along with the air and fuel then seen as nasty smelling and looking white smoke. When you pulled the vac line off the modulator was there tranny fluid present?  8)

Duh.... That makes sense. For some reason I was thinking it could only supply positive pressure. But if the pressure in the tranny exceeds the TB pressure, of course the fluid will get sucked up like a straw.

No fluid at all. Looked dry as could be.  I think the smoke is from the tranny fluid. (Based on smell and unless I am color blind is definately white) There is a ton of black soot (wet and goowie) coming out the tailpipe and splaterring on the back. I need to go out there and check the tranny fluid. I bet its really low.

Hopefully the transmission fluid will be severly low. (So that I will know most likely it is tranny fluid) Therefore since I don't know of any other way for the car to burn tranny fluid it must be the modulator thus if I let it run long enough it will stop.  The bottom of the tranny its dry so it probably doesn't leak fluid.

When I started this yesturday I drained the oil and filled it back up so I could tell if lots of oil was disappearing. I can't imagine all that soot and smoke being created by I small amount of oil (I check the level this morning at it was good). The soot litterally drips from the tail pipe and collects in a puddle on the ground. Maybe if I let it run longer and get it hot it will burn it all out and it will stop smoking.

BTW what does burning antifreeze smell like? (In case it is burning coolant) THat would suck to have a head gasket leak, I know coolant also looks white.

Let you know tonight...Thanks for your help

Ok, this may sound crazy, but when the car is running, but ur nose almost directly to the tail pipe. There will be a FAINT smell of coolant in it.  Heh, if it is a head gasket, have fun!  Been there, done that!

What exactly can a blown head gasket do to a motor? My car puffs white smoke and it puts out a litte fluid that collects in a puddle under the tail pipe.....just wondering

I must be color blind.....I went out this evening and first checked the oil cold.  The coolant looks good (not oily, not low).

Started it up and drove it in circles so I could try to get tranny warm. Let it idle and checked the tranny fluid. It was fine. Coughed a few times cause of smoke.  :D Then shut off the car and checked the oil again. The oil was down probably a 1/4 of a quart.   :x If anything it should have went up cause the fluid should expand when it gets warm.

Turned it back on and let it idle while I listened to the radio in a another car. After about 5 minutes the car started making noises. I think the noise is coming from the turbo.  :x Sounds like a faint metal on metal noise. Could it be the turbine wheel rubbing? It would only do it avery now and then. As I was putting my head closer to hear the noise I notice small puffs of smoke from the back of the turbo and a small oil spot in the small crack where the turbo housing meets the downpipe.

I think it is the Turbo. But I swear the smoke looks white.  :roll:

If what the dealer said was true that it started smoking after the tranny was put in....what could they have done to mess up the turbo?

Quote from: TimI must be color blind.....I went out this evening and first checked the oil cold.  The coolant looks good (not oily, not low).

Started it up and drove it in circles so I could try to get tranny warm. Let it idle and checked the tranny fluid. It was fine. Coughed a few times cause of smoke.  :D Then shut off the car and checked the oil again. The oil was down probably a 1/4 of a quart.   :x If anything it should have went up cause the fluid should expand when it gets warm.

Turned it back on and let it idle while I listened to the radio in a another car. After about 5 minutes the car started making noises. I think the noise is coming from the turbo.  :x Sounds like a faint metal on metal noise. Could it be the turbine wheel rubbing? It would only do it avery now and then. As I was putting my head closer to hear the noise I notice small puffs of smoke from the back of the turbo and a small oil spot in the small crack where the turbo housing meets the downpipe.

I think it is the Turbo. But I swear the smoke looks white.  :roll:

If what the dealer said was true that it started smoking after the tranny was put in....what could they have done to mess up the turbo?

it was probably just a coincidence w/ the turbo tearing up at nearly the same time as the transmission was put it, I doubt they messed it up.  How many miles are on the car btw? just curious...the turbo on my 740 died at 217K..give or take a few miles :oops:

EDIT: disregard the mileage question...read the first post again...DOH! :oops:

I had the same problem...I pulled my motor and rebuilt/replaced everything and sent out the turbo to Turbochargers.com for inspection and the housing was cracked and had it totally redone. My smoke was definately coming from the turbo seals and thru the exhaust and creating a wonderful haze effect whenever i stopped at a light! The car runs so clean there is no exhaust tinge at the outlet pipes and a totally dry floor under the engine bay. Good luck!

Normally white smoke in an Auto car is a failed Vac modulator from my experience. If you pulled the Vac Modulator hose that goes to the throttle body housing and you did not find any tranny fluid then you will need to look more at the turbo. You did say you replaced the Oil Return line that runs from the lower portion of the turbo to the oil pan right? Make sure that it is not kinked in anyway to restrict the flow of oil going back to the oil pan from the turbo. If it is not kinked and it is new...look for turbo shaft play. If you heard a metal to metal sound coming from the turbo area...then most likely you will find some play in the shaft. Chris A has a great right-up on how to check this... 8)

Yes, The oil return hose was replaced and it did not have any kinks, I check several times.  I did check the compressor  wheel for play and it didn't move.

I just got back in from removing the turbo.
Guess What!!
It had to be the problem...if not it definately contributed.
The back side(turbine side was caked with charcoal. I probably scraped several ounces of black crust with out even tuching the housing. I think its definately going to be a $750-800 rebuild ...if it can be rebuilt at all.

I may have messed it up even more since the last time I check the compressor spin with my fingers. Cause now when you rotate the shaft you can fill it slightly binding. But that may be because when I scraped the charcoal stuff some of the pieces may have fallen inside.

Thanks all you guys for your help narrowing down what the problem is.

Now Alll I have to do is decide where I am going to ship the turbo off to tomorrow.  And pay 700.00.