[msteele]

I got the code checked, and the result is 16683 Turbo/supercharger underboost. There is also oil on the intercooler, about halfway up. Any suggestions on how to proceed? I am 100 miles from a competent mechanic. (Most dont even want to fool with it)

 

[chittychittybangbang]

post moved to mk5 section since you have a 2005.5

Oil on the interior or exterior of the intercooler? Exterior could just be an oil leak getting blown around by the wind. Check the intake piping and connections. take a look through this checklist: http://www.myturbodiesel.com/1000q/multi/low-power-fix-TDI.htm and start working through it.

 

[msteele]

re. Low power

The code we got from the reader indicated a "low boost" condition. My actuator is electrically controlled and is moving when you rev the engine. Also a fair amount of oil drained from the tube below the intercooler. Test driving again it seemed to be working properly at times but not continuously. W.T.F?

 

[chittychittybangbang]

It's only semi electrically controlled, it is vacuum controlled from a solenoid. The black thing on the end is a sensor to detect its position.

A light splash of oil in the intake is normal and is from the crank case vent. It settles in the low spots. A cupful is too much and could indicate a bigger problem like a blown turbo.

 

[msteele]

Well, it probably was not a cup but way more than a splash. I am now looking for a new turbo, and I thank you for your assistance with this issue and I am quite pleased that this forum works as it does. Minor gearheads like me need this stuff.
Thanks again.

 

[chittychittybangbang]

If you drive with a light foot, maybe a 1/4-1/3 cup is OK. If you step on it, this is good for the engine, it will blow out the buildup in the intake and also help burn up and blow out the buildup in the engine and exhaust/turbo. I wouldn't get a new turbo just yet, I would do some more digging around the engine bay. Yes it's possible to have a bad turbo but most of the time it's something else.