busted wastegate or tired turbo?

[Dirtrag2]

I hooked a boost guage up to my '97 jetta and to my surprise there was no boost tot be seen  :shock:  turbo in my ride should be a K-03 if my research is correct.
can it be the wastegate? if so should I think of upgrading turbo or fix the wastegate?   also what turbos bolt up to my engine?

thanks

[andy2]

Were you checking boost pressure as you felt that there was a low power condition?

Also where did T into for the boost signal?

The k03 turbo's wasegate is the best one of them all so I'd be suprised to hear that it had an issue.If the turbo is no good they usually end up pushing oil into the exhaust causing lots of blue smoke.

[Dirtrag2]

I T'ed in on the rubber hose running from my intake manifold to the fuel pump. ( correct no ? )

I had the engine completely rebuilt a couple of months ago by my long trusted vw mechanic, he told me the wastegate was partially seized but should still be ok.
Naturally now that I have put 3000 km on engine I've tweaked pump and was  about to up the boost when... NO BOOST^^

any suggestions?

Edit: ps. no blue smoke

[Vincent Waldon]

Two suggestions:

- Were you driving when you were checking the boost ?   Many many people hook up the boost gauge in the garage and then rev the engine and are surprised by a lack of boost.  Sitting in the driveway you will have no boost because the engine is not producing excess heat.... the engine needs to be working.

- Is the turbo spinning ??  Pull the intake air hose off the turbo and then check with a flashlight while the engine is running to see if the impeller is spinning.


If the turbo is spinning and you have no boost under heavy acceleration then the usual cause is a wastegate that is seized in the "open" position, thereby dumping all the boost.  If it is was seized in the closed position you'd be getting lots of boost.  :wink:

[Dirtrag2]

just reinstalled the gauge permanantly and went for a ride, I live in a hilly area so lots of hills to climb, here are the results:  in 3rd thru 5th beetwen 3500 and 4500 RPM I got a reading of 3psi when pulling hard, other than that, nothing.

Checked and the impeller turns freely, a bit of side play ( about 1/16th inch total )

looks like the wastegate, any suggestions? should i pull it off and fix it or just upgrade turbo to a K24 or T3?

[zukgod1]

Well you can check to make sure the hose you tee'd into isn't partially plugged and go from there. could be nasty on the inside of the manifold plugging it off, this would affect more than just the gauge as the LDA wouldn't be receiving a boost signal either which would give you low boost levels because of low fuel delivery under hard accel.

[jtanguay]

you also need to check if the boost pressure is leaking... if the wastegate is seized open then it would act like you describe...

[Dirtrag2]

I replaced the ruber hose from manifold to LDA, also checked the spout in manifold air comes thru when engine is running so i doubt it is gummed up.

same end result 3psi  

[jtanguay]

one thing you could possibly check is the turbo shaft play.  you'll need to disconnect the air hose going to the compressor.  you want to check up down play and then side to side play.  side to side play is much worse than up/down play.

[zukgod1]

I'm going to vote for stuck open waste gate

[jimfoo]

or possibly a loose hose between the intake and turbo, or a hole.

[mud and diesel]

Have you tested your boost gauge on anything else? checked all hoses for leaks?

[Dirtrag2]

i hooked a bicycle pump to Boost hose and gauge works fine. also no holes/leaks beetwen turbo and manifold.

I was thinking of upgrading my turbo soon anyway, it's a k03, what is a direct bolt on replacement?