problems, loss of oil and struggles past 3000 rpm

Tuned up the car(timing, belts, oil, air) when I got it 6000 miles ago (now has 116000), and ever since (don't know if it was happening before) I have been losing about 1qt/500 miles. Hmmmmm, where is this oil going????? someone suggested that the turbo seals may be going out, causing oil to be pushed past them, and into the intake tract, getting burned off during combustion. This makes sense to me because my PCV hoses are oil-soaked, and I took off the hose that leads from the turbo to the intercooler, and it too was oil soaked, I put my fingers in there, and they came out dripping with oil. Probably the turbo, right???
Well, just about 200 miles ago, I have noticed a surging/hesitation/struggle between 3000 and 4000 rpm's under load, I tried new injectors and a fresh fuel filter, but it still persists. So maybe that also could be the cause of a turbo going bad??? Further suggesting bad seals is a coat of oil on the intake just behind the metal-to-rubber turbo output joint, suggesting that under boost, a fine mist of oil is being pushed pat the clamps and onto the intake.
Now, it doesn't hesitate without load, if I am in neutral, it will go to 4000 rpm's nice and smooth, but under load is where I get the hesitation at ~3200-4000 rpm. ANyone have any clues??????

What you need to do is this: Take the intercooler pipes out of the car and THOROUGHLY clean them out. Also, THOROUGHLY clean out the intercooler (see instructions in FAQ). Get them spotless and bone dry. Dissolve the crap out with kerosene, do it a couple of times until it runs clear, then get rid of any oily film using dish detergent and hot water. Helps to agitate the stuff in the intercooler by blowing air through the solvent. Get all the liquids out, then re-assemble.

Now, temporarily disconnect your crankcase vent (which is where the oil contamination normally comes from). Run a 3/4" hose from the black housing to somewhere, and plug the existing hose with a 3/4" plug. You now know that nothing from the crankcase vent will be contaminating your intake system.

Drive like this for a little bit, then periodically check the intercooler pipes at a convenient location (preferably BEFORE the intercooler). If any oil shows up in there, the only source is either (1) you didn't clean them out well enough, or (2) the turbo seals.

The other thing you can check is how much blowby your engine has, by feeling the end of your open crankcase vent hose. Do this with the engine fully warmed up (it will always leak more when it's cold, that's normal). Disregard the pulsating in-and-out and note whether there is quite a bit of "net" outflow. (Mine has practically NO blowby once warmed up, and that's at 243,000 km.)

I would be surprised if the turbo seals have anything to do with it.

Betcha your intake manifold is clogged, in addition to all of the above. Feel free to take it off the engine and clean it out as part of the above process (you have to take off the intercooler pipes to do this one anyway).

Is this an A3, B4, or A4?

too much timing may also cause this. Since it started after you got you timing done. Maybe it slip and is way out of spec.

Thanks for the reply guys.
GoFaster, this is the same car as you have, a '96 TDI Passat, and the intake was thouroughly cleaned, even powder blasted when I did the timing. But I will take your advice and clean everything and reroute the CCV.

Oldamn, how ya doin'. I have a friend down the road from me (Drivbiwire), I will see if he can hook up his VAG and check the timing, I thought about that too, especially with the hesitation past 3000 rpm, thanks again, keep posted.

I think your turbo is toast. Is it a KKK or a Garrett?

-mickey

Originally posted by mickey:
I think your turbo is toast. Is it a KKK or a Garrett?

-mickey

Click to expand...

<font size="2" face="Verdana, Helvetica, sans-serif">KKK

Gintaras I can't remeber if you had the KKK or the Garrett.

I'll be doing some stuff at my place in the AM on Sunday around 10:00, walk on over and we can do some trouble shooting then you can walk back and try some things...(Don't you just love it when people on here are really neighbors )

Bkmetz will be over with his 97 Passat so we can have a mini Passat TDI GTG. We are replacing a CV joint and maybe you can help with your boot experience.

DB

[ March 02, 2002, 06:08: Message edited by: Drivbiwire ]

Originally posted by Drivbiwire:
Gintaras I can't remeber if you had the KKK or the Garrett.

I'll be doing some stuff at my place in the AM on Sunday around 10:00, walk on over and we can do some trouble shooting then you can walk back and try some things...(Don't you just love it when people on here are really neighbors

)

Bkmetz will be over with his 97 Passat so we can have a mini Passat TDI GTG. We are replacing a CV joint and maybe you can help with your boot experience.

DB

Click to expand...

<font size="2" face="Verdana, Helvetica, sans-serif">OK, will be there.

If that car really has the KKK turbo and not the Garrett, I would be really surprised. But if it really IS the KKK, check with your VW dealer. They had a recall on early '96 models to replace the KKK with the Garrett.

Originally posted by GoFaster:
If that car really has the KKK turbo and not the Garrett, I would be really surprised. But if it really IS the KKK, check with your VW dealer. They had a recall on early '96 models to replace the KKK with the Garrett.

Click to expand...

<font size="2" face="Verdana, Helvetica, sans-serif">I am probably wrong, I don't know what it has, I'll find out 2morrow.

Gintaras came over and we found a couple of things. The car gets a slight surge above 3,000
rpm and loses a bit of power. The car is using a lot of oil. The other night he came back from Michigan and used 1.5 quarts.

I had Gintaras pull the turbo so we can inspect the turbine and compressor for play and possible damage. The compressor had some play but not enough that I would consider it excessive simply going by feel. I'd have to look up the tolerances to perform a runout test. But before we looked those up we pulled the turbine housing off and inspected the turbine guess what we found...all the turbine tips are curled over Pictures will follow.

He has only had the car for 15,000 miles and was purchased at 100,000 with an unknown history. The engine has no blowby and no residues as far as we can detect coming from the CCV vent which is still hooked up.

More to follow.

DB

[ March 03, 2002, 15:04: Message edited by: Drivbiwire ]

Thanks for the summary DB. I bought the car at 110000 miles in December, and it now has 117000, just FYI. I am really interested in finding out the condition of the seals inside the bearing/seal unit, so let me know when you tear it apart. Well, we'll see, this should be interesting, thanks for your help today.

[ March 03, 2002, 17:27: Message edited by: gintaras ]

The good thing is we know that the engine is in good health based on the lack of flow out the CCV when the engine is running not to mention the great power it has down low.

I suspect that when the turbo would get spooled the out of balance was wearing away at the turbine side of the bearing. This probably created enough movement that oil could work past the compressor seal and creat the smoke. I feel confident that there is very little oil leakage at the turbine because of how dry the turbine area was and the lack of coking.

The compressor housings puddle of oil is another good indicator that something is not right there.

The good thing about finding this now is that we won't have to read about you in the runaway section...

DB

more later
DB

Damn Pete, did you really have to use an electron microscope?!?!?

What is the first pic?? Looks like an extreme close up of the end of a blade.

did you get a chance to open it up and check out the seals???

[ March 04, 2002, 17:35: Message edited by: gintaras ]

whoa, houston, we have a problem!

yikes, wonder what spiked the EGT ... ? ? ?

Originally posted by GoFaster:
whoa, houston, we have a problem!

yikes, wonder what spiked the EGT ... ? ? ?

Click to expand...

<font size="2" face="Verdana, Helvetica, sans-serif">I know it shouldn't, but would sustained 90mph do it???

The Replacement Turbo is on the way To Pete!
The 70,000 mile GT-15 off my Passat will soon
make new residence!

Originally posted by tomo366:
The Replacement Turbo is on the way To Pete!
The 70,000 mile GT-15 off my Passat will soon
make new residence!

Click to expand...

<font size="2" face="Verdana, Helvetica, sans-serif">Thanks! It will be in good hands

Originally posted by GoFaster:
whoa, houston, we have a problem!

yikes, wonder what spiked the EGT ... ? ? ?

Click to expand...

<font size="2" face="Verdana, Helvetica, sans-serif">Brian do you think the oil at sustained high rpms could have caused temps to go that high? What if the oil is not burning completely and in essence afterburning in the exhaust. The burning oil droplets could account for hot spots ont he tips of the turbine. Also as the efficiency decreased the ECU was commanding more boost higher back pressure, thus causing the temps to go even higher. This turns into a rapid failure pretty quick.

This turbo will make for some good conversation!

I have not pulled the shaft yet too many projects today and tommorrow. I should have the time to tear it down on Thursday for you. There is a lot of play on the turbine side and I really think this is your problem. The oil puddling in the turbo could also account for the smoke at start up and rough running you have been having. The oil since its not controlled is pre-igniting throwing your combustion cycle off. I would just about bet that the thrust bearing has a lot of wear from the shaft moving around.

I would not worry about the sustained speeds at 90mph, thats what these cars are made for (but with good turbos).

I'll inspect the new turbo before we install it just to make sure everything is ok and then I'll have you come over and get to install it. With a bit of luck we will have you up and running on Wednesday night.

DB