Turbo Waste Gate not closing properly


#1

I have a 2006 Volkswagon Jetta GLI and when the check engine light went on I took it to my local car guy. He said the Turbo Waste Gate isn’t closing properly and I should take it to the dealer to see if it can be repaired or if it has to be replaced. He told me could replace it if that’s what’s needed but he can’t repair it but I can still drive it probably just for a few months before it needs to be fixed.

I need to drive from Minnesota to Washington State in the next few weeks so I think I need to do something before I go. How critical is this and what does the turbo waste gate actually do? Thanks for any help you can give me!!


#2

A wastegate is a valve that sits in front of the turbo compressor.

Here, let’s go over how a turbo works, and then it’ll make sense:

As you drive, exhaust exits the engine and heads down the exhaust pipe to exit out of the muffler. You can think of exhaust as wind going through the pipe.

Much like a windmill, a turbo uses a turbine to capture that wind energy. It then spins a turbine that’s sitting in the air intake, which acts as a pump to force more air into the engine than it would get normally. The engine uses that extra air to burn more fuel, which makes bigger explosions, which gives you more power.

But if you go overboard on this, and introduce too much pressure in the intake (this pressure is called “boost,”) then you start breaking things.

That’s where the wastegate comes in. Once the pressure gets to a preset limit, the wastegate starts opening, which channels some of the exhaust flow away from that turbine, so that it doesn’t spin too fast and create too much boost.

If your mechanic is right and the wastegate isn’t closing properly, then this means that it’s redirecting exhaust flow before the pressure gets to that limit, which means that you aren’t getting as much boost as you should be getting.

The end result in this is that your car is going to be slower. When you’re tooling around on those mountain roads in Washington, it’s going to be a lot slower than it should be.

However, this isn’t a situation that should damage the car - but it is something you’re probably going to want to replace at some point so you can get that lost power back.


#3

Thank you!! I’ll have it fixed before I leave but it’s good to know that it’s not urgent. One thing I really love about this vehicle is the power it has…and so far it doesn’t seem to be slowing down. Again, thanks for the advice…much appreciated!


#4

Most cars with turbos have a boost gauge on the dash that gives some indication of boost level…(The ONLY time the engine gets boost is during WOT (wide-open-throttle) operation. When accelerating at full throttle, see if the boost meter goes up near its maximum reading. If it does, then the waste gate diagnosis might not be correct…However, it the meter indicates a possible over-boost condition, then yes, that can lead to engine damage because the gate is not opening as designed…


#5

Thanks, Caddyman. So can anyone give me an idea about how much it will cost to fix this? Or if it needs to be replaced?