Smoke at startup, increased oil consumption in ALH

[MichaelP]

I have a 2000 Jetta ALH 5-speed with 269k miles. It has had a custom Kerma tune since around 130k miles. I recently had an issue with reduced power which turned out to be a bad MAF sensor, but not long after fixing that it started smoking a lot intermittently at start-up (light gray smoke with a burned oil smell) and consuming more oil. I already had a leak from somewhere around the turbo, but it was only losing about 1 qt every 5k miles, but with this sudden smoking it increased to 1.5 qts in 1000 miles. I plan to dig into it this weekend.

After reading a few threads it sounds like valve seals are an unlikely issue (due to the lack of intake vacuum). What else should I be checking? I planned to pull the tubes and check for oil in the turbo and intercooler. Before this I planned to change to a cleaned intake manifold this weekend (and still may do that depending on what I find).

 

[steve6]

I have a 2000 Jetta ALH 5-speed with 269k miles. It has had a custom Kerma tune since around 130k miles. I recently had an issue with reduced power which turned out to be a bad MAF sensor, but not long after fixing that it started smoking a lot intermittently at start-up (light gray smoke with a burned oil smell) and consuming more oil. I already had a leak from somewhere around the turbo, but it was only losing about 1 qt every 5k miles, but with this sudden smoking it increased to 1.5 qts in 1000 miles. I plan to dig into it this weekend.

After reading a few threads it sounds like valve seals are an unlikely issue (due to the lack of intake vacuum). What else should I be checking? I planned to pull the tubes and check for oil in the turbo and intercooler. Before this I planned to change to a cleaned intake manifold this weekend (and still may do that depending on what I find).

this is all you really need to do "I planned to pull the tubes and check for oil in the turbo and intercooler." it will most likely contain your answer. 1 qt in 5000 miles is 'normal' or marginal, but 1.5 qts in 1000 miles is too much. Check your intercooler before it sucks in oil and causes a run away.

 

[maxmoo]

Check for play in your turbo.

 

[ghohouston]

If your turbo checks out, it probably is valve stem seals. You can pull the turbo/exhaust manifold and look at the exhaust valves. It will be obvious if one is leaking.

 

[MichaelP]

Thanks for the input! Intercooler and tubes have a bunch of oil in them, presumably the turbo's oil seals are worn out?

Where is the best place to get a low mileage or rebuilt stock turbo? Isn't the stock one a VNT15? I suppose I would consider an upgrade at this point, but I mostly want to get it back together quickly.

 

[flee]

You can't go wrong with a new Mahle VNT-15.
I bought one from IDParts a few years back.

 

[BobnOH]

Thanks for the input! Intercooler and tubes have a bunch of oil in them, presumably the turbo's oil seals are worn out?....................

That's always tricky because if the car is driven gently combustion gas precipitate will collect, it's oily. Does sound like the turbo might be leaky though, verify. Some folks get away cheap with turbo replace, more not so much.