Turbo rebuild

Can anyone recommend someone that can repair/rebuild the turbo for my 2000 Jetta? I am installing a boost gauge and when I took the intercooler pipe off I saw a fair amount of oily residue. I am afraid that an oil seal of some kide is failing in the turbo. When I removed the intercooler last year I found old oilk had accumulated in it.

Thanks

2000 Jetta, 172500 mi, manual trans

It is common to have an oily residue in the intercooler and associated pipework. It comes from the CCV system. It pays to run the motor hard a couple of times a week to help clear it all out.

When I took my intercooler pipe off a few years back, I must have had around 10cc of oil in it. I was worried until I checked out this forum. My car and turbo have been fine.

Is this the only reason why you think you need a turbo rebuild or are there some other sypmtons e.g. Is the car using lots of oil etc?

No not using oil, but I did just install a boost gauge and it seems like I am not getting much boost out of it

Fireguy2008 said:

No not using oil, but I did just install a boost gauge and it seems like I am not getting much boost out of it

Click to expand...

How much boost do you see?

Chances are it's not the turbo per-se but something else: N75, vacuum lines, actuator, vanes themselves.

It would be worthwhile plotting the boost using VCDS and checking to see if it matches requested boost. Also check to see if the new boost gauge is actually reading correctly, you could rig up something to pressure test this with an adapter connected to a known pressure source e.g. tyre inflated to say 5, 10, 15, 20, PSI etc.

Does the car feel slugish or smoke a lot?

As the other guy says I would check all the turbo control mechanisms first, I don't think the actual turbos tend to fail by supplying less boost. They normally fail with a major fault like oil seal/shaft failure and dump all the oil into the intake with potentially fatal consequences from a run away and hydro lock etc.

Also I have experience with failing MAF sensors that start to reduce power and feel like loss of turbo pressure.

Ok, I took the car for a spin and I ran it through a variety speeds, acceleration etc. I am not sure if the amount of boost is correct or not. Anyway here it goes. At Idle- 0psi, 1500rpm- 0, 2000- 0, 3000-1-2, 4200 4-5 psi. When the RPM's come up when I downshift, there is no change in boost. From a stop under gentle acceleration no boost, moderate acceleration there is a rapid jump to 15 hten a rapid drop to about 7- 10 then a steady drop to 0.With the accelerator to the floor there is a spike to 20 then the slow drop back. When cruising on the highway at 65 mph (2200 rpm) there is 0- 2 psi, 70mph (2400rpm) 1-2, 75 (2600 rpm) 3-4 and 80 mph (2800 rpm) about 4 psi of boost. Now when on cruise on the highway at 65 and there is more of a load on the engine like climbing a hill, the boos increases to about 5- 6 psi.

What do you guys think?

This doesn't sound right to me, sounds too low for most of the time.

First how are you measuring the boost?

If it is by using just your new boost gauge then have you checked it is reading correctly first? If not the rersults could well be meaningless.

The best way to check boost is to use Vagcom (VCDS) and plot requested versus actual. Do you have Vagcom?

Also, if your boost is too low, I would expect the car to smoke a lot and be down on power. Have you recently noticed a power drop, what is the history on the car?

If the boost is confirmed to be too low then you need to check the VNT mech on the turbo is not jamming up and that the vacuum diaphram is not leaking etc. If this proves OK then move back to the N75 valve and associated vac lines checking for leaks etc.

ALso check for any splitting hoses from the turbo to the intercooler, to the EGR valve etc as you could be loosing any boost the turbo is making through a hose or union leak. Do you notice any air leaking/rasping noises when you rev the motor?

I just installed a boost gauge that I purchased from New South Performance. I drilled and tapped the intake pipe just before the rubber elbow that enters the EGR valve. It is a very tight fit and I don't think that I am losing any boost at any of the connections. I do not have Vagcom although I am hopint that I will be able to connect with someone who does in the near future. Not much smoke, and the car feels like the power isn't bad, but I admit that since it was 8 years old when I bought it, I don't know if it has lost any power over time. I do not hear anything that sounds like an air leak either. I guess I need to find out if the gauge is reading accurately or not.

Fireguy2008 said:

Ok, I took the car for a spin and I ran it through a variety speeds, acceleration etc. I am not sure if the amount of boost is correct or not. Anyway here it goes. At Idle- 0psi, 1500rpm- 0, 2000- 0, 3000-1-2, 4200 4-5 psi. When the RPM's come up when I downshift, there is no change in boost. From a stop under gentle acceleration no boost, moderate acceleration there is a rapid jump to 15 hten a rapid drop to about 7- 10 then a steady drop to 0.With the accelerator to the floor there is a spike to 20 then the slow drop back. When cruising on the highway at 65 mph (2200 rpm) there is 0- 2 psi, 70mph (2400rpm) 1-2, 75 (2600 rpm) 3-4 and 80 mph (2800 rpm) about 4 psi of boost. Now when on cruise on the highway at 65 and there is more of a load on the engine like climbing a hill, the boos increases to about 5- 6 psi.

What do you guys think?

Click to expand...

I want to clarify your knowledge as it seems you were expecting boost to be there all the time. The turbo will produce boost only under a load. If you are gently accelerating or cruising, you will see no boost to a few PSI. If your vehicle has stock nozzles and ECU then 12-13 PSI is the most you should see. You will have a spike in boost when first accelerating very hard but 20 is a little too high, maybe 15-17 PSI. If you do have a tune and/or larger nozzles then add 5 PSI (about) to the numbers above.

Duster408 said:

I want to clarify your knowledge as it seems you were expecting boost to be there all the time. The turbo will produce boost only under a load. If you are gently accelerating or cruising, you will see no boost to a few PSI. If your vehicle has stock nozzles and ECU then 12-13 PSI is the most you should see. You will have a spike in boost when first accelerating very hard but 20 is a little too high, maybe 15-17 PSI. If you do have a tune and/or larger nozzles then add 5 PSI (about) to the numbers above.

Click to expand...

Ok, thanks for the info. I was expecting to see at least some boost all the time. I think that I will still try to find someone with Vagcom to verify that the amount of boost that is delivered is the amount that the ECU is requesting. The system is pretty much stock, there is a performance programmer that the previous owner installed that I have just left in place and I have straight piped it, but otherwise the turbo, nozzles and other engine components are stock.

google malone tuning. he has a procedure to follow to log your runs while using the vagcom so you can send them to him and he can give a quick look into what your turbo request/actual is...

vagcom locator is at the top of the screen